System for cardiac resuscitation

ABSTRACT

System and method for monitoring and controlling, defibrillation and pacing which allows a victim of a cardiac rhythm abnormality immediate access to a medical professional at a central station, who will remotely monitor, diagnose and treat the victim at one of a plurality of remote sites in accordance with the following steps:
         (1) providing a plurality of contact electrodes for a victim at a remote site for the receipt of ECG signals and for the application of electrical pulses to the victim;   (2) transmitting the signals from the remote site to a central station and displaying them for review by the medical professional;   (3) the medical professional selecting from a menu of defibrillation and pacing pulses, if the application thereof is appropriate;   (4) transmitting the selection results to the remote site; and   (5) receiving the selection results at the remote site and applying the selected pulses to the victim.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional application of U.S. patent applicationSer. No. 11/893,897, filed Aug. 18, 2007, now pending, which, in turn,was a divisional of U.S. patent application Ser. No. 10/460,458 filedJun. 11, 2003, now U.S. Pat. No. 7,277,752.

BACKGROUND OF THE INVENTION

Sudden death from cardiac causes, often due to heart rhythmabnormalities such as ventricular fibrillation (VF) and ventriculartachycardia (VT), claims approximately 225,000 persons annually in theUnited States (1999 Heart and Stroke Statistical Update—Dallas: AmericanHeart Association, 1998 or approximately one per 1,000 population peryear.

Nationwide, only two to five percent of those who suffer anout-of-hospital cardiac arrest are saved (New England Journal ofMedicine 2000; Vol. 343: Pgs. 1259-1260). In grid-locked cities like NewYork City, analysis of the Emergency Medical Service/Fire Departmentdata has shown that less than 1% survive the ordeal. Because of theabysmal survival rate, the first arrest is almost always the last.

Cardiac arrest is the abrupt cessation of the heart's mechanicalfunction leading to loss of consciousness and the rapidly progressingsequence of heart and brain deterioration, irreversible heart and braindamage, and death. This cessation of mechanical function during anarrest is often caused by a sudden chaotic deterioration in the heartrhythm referred to as ventricular fibrillation (VF) or by the suddenonset of a very rapid and mechanically ineffectual rhythm calledventricular tachycardia (VT). In either case, the heart's normalfunction can usually be restored by a prompt and properly administeredelectrical shock to the chest, generally referred to as defibrillation,or by application of synchronized electrical pacing signals.

It has been estimated that once an arrest has occurred the mortalityrate increases by 10% per minute until definitive therapy commences. Iftreatment has not yet commenced ten minutes into a cardiac arrest, thereis little likelihood of recovery. The evidence that the response timehas a profound influence on the rate of successful resuscitation comesfrom two types of analysis: a) comparisons among studies in which theresponse times were different; and b) comparisons within studies, wherethe results of a short response time are compared to a longer responsetime, within the same population. The discussion of comparisons amongstudies follows.

Data from New York City and Chicago illustrate the poor resultsassociated with a long response time. There are an estimated 7,000incidents of cardiac arrest each year in New York City alone. EmergencyMedical Service figures during a five year period—1994-1999—revealedthat a total of only 168 patients were successfully resuscitated. Theaverage EMS response time, from the time the service was summoned, wasreported to be seven minutes. Based on the 10% per minute mortalityestimate, one would expect a 70% mortality for a 7 minute response time.The EMS survival figures are much worse than would be expected based onthe ten percent per minute mortality estimate. The reason may be thatthe time from the event onset until actual defibrillation issubstantially longer than the 7 minute EMS dispatch and transitinterval. This prolongation includes delays: a) from the moment of onsetof arrest until EMS is called (referred to below as the “pre-call”interval); and b) from the time of EMS arrival until life-saving therapyis begun (referred to below as the “pre-shock” interval). Even if thesum of these delays is only three minutes, the expected resuscitationrate plunges to a negligible value, and is consistent with the observedvery low survival rate. In Chicago (population over 3 million [linearinterpolation of 1980 and 1990 census data]; area 228 square miles) thereported results, though slightly better than in New York City, are poornevertheless. Becker et al. report that 91.4% of patients were dead onarrival at the hospital; 6.8% died in the hospital and 1.8% weredischarged alive (New England Journal of Medicine 1993; Vol. 329: Pgs.600-606). The response time, defined as the interval from the 911 callto the arrival of the ambulance (referred to below as the“call-to-arrival” interval) ranged from 1 to 22 minutes; the median was6 minutes.

Improved response times are obtained by so called “code teams” in ahospital setting. An analysis of data from Kaye et al. showed that 9.5%of 210 hospitalized patients who suffered a cardiac arrest survived toleave the hospital (Circulation 1999; Vol. 100: Abstract 1645, pageI-314). Eisenberg indicates that survival rates for inpatient cardiacarrests have been reported to range from 0 to 29% (New England Journalof Medicine 2001; Vol. 344: Pgs. 1304-1313). The higher survival ratesare attributable to faster reaction times in the hospital environment.

Still better results are reported from King County, Wash., where theemergency response system is unusually sophisticated. Sweeny describes a30% survival to discharge figure (Annals of Emergency Medicine 1998;Vol. 31: Pgs. 234-240) for this group. Similar results are reported fromRochester, Minn. (1993 population 76,865; area 32.6 square miles); Whiteet al. report the results of 158 cardiac arrests between 1990 and 1995.An analysis of their data, in which the survival to hospital dischargeis calculated for all arrest victims shows the value to be 26%. Theymake a more meticulous effort than some prior investigators to defineand measure their response time, and they used the “call-to-shock”interval. Analysis of their data shows the value to be 6.0 minutes. (Theaforementioned Chicago data was based on a 6 minute “call-to-arrival”interval. The call-to-shock interval is the sum of the call-to-arrivalinterval plus the pre-shock interval.)

Gambling casinos are an ideal locale for the analysis of therelationship between response time and outcome for two reasons: a)because of the ultra-high level of scrutiny, the time of onset of arrestcan be known accurately; and b) because of the high level of stress forsome patrons, the arrest rate is enhanced. Valenzuela et al. report on aprogram in which casino security officers where trained and equipped torapidly defibrillate arrest victims (New England Journal of Medicine2000; Vol. 343: Pgs. 1206-1209). There were 148 patients who suffered acasino cardiac arrest in 10 casinos in Nevada and Mississippi during theyears 1997-1999. Fifty six victims (38%) were resuscitated and survivedto hospital discharge. The interval from “collapse-to-shock” was 4.4minutes. It represents a very short response time since it is the sumof: (a) the call-to-arrival interval (used in the Chicago study), plus(b) the pre-shock interval, plus (c) the pre-call interval. (The 6minute Minnesota result was based on call-to-shock, i.e. (a) plus (b).)The interval from collapse to paramedic arrival was 9.8 minutes, which(without early defibrillation by the security officers) would beexpected to result in a negligible survival rate.

The two keys to high arrest survival rates are a short interval fromonset of arrest until provision of defibrillator shock, and the presenceor rapid arrival of expert medical personnel at the arrest site. Thecompelling nature of the relationship between response time and successrate is further demonstrated by comparisons within studies.

The Rochester study divided victims with ventricular fibrillation (84 ofthe 158 arrests) into two groups: one group resuscitated by the police,whose call-to-shock time was a mean of 5.6 minutes, and one resuscitatedby paramedics, whose call-to-shock time was 6.3 minutes. The fraction ofa minute difference in arrival time impacted the survival rate. In thepolice group, 58% survived to hospital discharge; in the paramedic groupwith the slightly delayed arrival time, 43% survived to hospitaldischarge. (These survival values are larger than the previouslymentioned 26% because that value included other arrest victims [i.e.,victims with asystole and pulseless electrical activity] who are farless likely to be resuscitated than victims with VF.)

The casino data also gives firm support to the relationship betweenquick shock and hospital survival. Again, looking only at the VFvictims, of those who received their first shock in less than threeminutes, 74% (26 of 35) survived to hospital discharge, whereas only 49%(27 of 55) who were shocked after three minutes survived to hospitaldischarge.

The best results, in terms of resuscitation rate, occur in the hospitalcardiac electrophysiology testing laboratory. Here, during the conductof arrhythmia evaluations (referred to as electrophysiologic studies) inhigh risk patients, life-threatening VT and VF are frequentlyencountered. However, because of the presence of trained highlyexperienced arrhythmia physicians and nurses at the procedure, andbecause of the very short response time (time from onset of VF untiltime of shock is usually less than 15 seconds), the resuscitation rateis significantly greater than 99%.

The near 100% resuscitation rate in the electrophysiology laboratoryrepresents an ideal that is not likely to be reproduced outside of thelaboratory because:

a) the arrests in such a laboratory are all due to VT and VF, notasystole or pulseless electrical activity;

b) these arrests are artificially induced; hence, they are primaryelectrical disturbances, not electrical disturbances secondary to someother process, such as the sudden blockage of a coronary artery;

c) the response time is extremely short; and

d) doctors and nurses specializing in heart rhythm treatment are presentat the procedure.

Nevertheless, the electrophysiology laboratory data does show there isnothing about VF per se that implies its irreversibility. As long as theresponse time is very short and the VF is not secondary to a suddencatastrophic structural problem (such as the abrupt blockage of anartery within the heart), we can expect a very high success rate. Thisconcept is supported by the resuscitation results in patients withimplantable cardioverter-defibrillators, which automatically detect andterminate VT or VF. Their response times and success rates, forspontaneously occurring VT and VF are comparable to those of theelectrophysiology laboratory. The high success rate for very prompttermination of VF was confirmed in an entirely different setting. Pageet al. report initial termination of VF in 13 of 15 (87%) patients whowere treated as part of an effort to provide commercial airliners withdefibrillators (New England Journal of Medicine 2000; Vol. 343: Pgs.1210-1216).

As the time until shock increases, two types of events seem to occurwhich markedly reduce the chance of success. First, there is evidencethat the longer the response time, the smaller is the fraction ofpatients actually found to have ventricular fibrillation. In otherwords, it may well be that in the moments immediately after anout-of-hospital arrest, the fraction of patients with VT or VF among allarrest victims is high; and that as the minutes go by, that fractiondecreases. In the casino study, with its very short response time, 71%of victims had VF. In the Rochester study, with its intermediateresponse time, 53% had VF. In the Chicago study, with its long responsetime (since the 6 minute reported response time included only thecall-to-arrival component), 22% had VF (calculated from their data). Thefraction of victims with VF is important because among arrest causes, VFis far more likely to be treatable than either asystole or pulselesselectrical activity. (In the Minnesota study there were 74 non-VFvictims; and in the casino study there were 43; none of these non-VFvictims were resuscitated.)

The second deleterious event which occurs very quickly during VF is theonset of irreversible mechanical damage to the heart muscle. Once suchdamage occurs, the chance of survival to hospital discharge plummets.The Minnesota study analyzed this by looking at a predictor of survivalthat they called “ROSC,” restoration of spontaneous circulation. ROSCwas defined as present when either no cardiopulmonary resuscitation(CPR), or less than one minute of CPR was required. Victims with ROSCalso did not require any medication to support their blood pressure.ROSC was a powerful predictor of survival to hospital discharge. Twentyseven of 28 victims (96%) with ROSC survived to hospital discharge; 14of 56 without ROSC survived to discharge. The police with their 0.7minute earlier arrival time had a much higher ROSC rate (42%) than didthe paramedics (28%).

Automatic external defibrillators or AEDs were used by the police in theMinnesota study. They were used in the airline study and by the casinosecurity officers. These AEDs are intended for use by minimally trainedpersonnel. AED electrodes, which must be properly placed in contact witha cardiac victim's chest wall, allow the device to analyze theelectrocardiogram (ECG) signals of a cardiac victim. Based on the ECGsignal information which it receives, the AED automatically applies ahigh defibrillation voltage to these electrodes when its algorithmdetects VT or VF. The decision to shock or not to shock, and themagnitude of the voltage application, are determined by circuitry withinthe device.

A number of systems are known which provide automatic externaldefibrillation. Equipment of this type is currently distributed byMedtronic Physio-Control, Philips and Cardiac Science, and may bepurchased at a cost of about $2,500-$3,000 per unit. This equipment isnow intended to be made available at places such as governmentbuildings, casinos, airports, office buildings and sports arenas, and tobe carried upon public modes of transportation such as commercialairliners. There is an increasing effort to have them carried aboardpolice cruisers.

The advantage of AEDs is that they allow a decreased response time byempowering non-medical people who can arrive sooner than paramedics totreat a cardiac arrest. In the Minnesota study, most police cars carriedAEDs; they arrived sooner than the paramedics; and they had betterresults. In the casino study, cited above, security officersdefibrillated with AEDs at a mean of 4.4 minutes after victim collapse;the paramedics arrived at a mean of 9.8 minutes after collapse.

On an airliner, the chance of arrest survival without on-board treatmentis nil. The cardiac arrest survival rate in Boston increased from 16% to24% when the number of AEDs was increased from 85 to 185 and all 1650firefighters were trained to use AEDs and to perform cardiopulmonaryresuscitation (Circulation 1998; Vol. 97: Pgs. 1321-1324).

Although AEDs have improved survival by decreasing response time theycannot be considered to be the ultimate solution because they lackcertain important advantages that a highly trained medical professionalpossesses. The transfer of a responsibility, which traditionally lieswithin the domain of the medical profession, to the AED and its operatorresults in or fails to completely address seven classes of potentialproblems:

a) the limitation of proper AED performance to conditions addressed byits algorithm;

b) the necessity of assuring the proper electrical interface between theAED and the victim;

c) the persistence of delays not entirely circumvented by the AED;

d) the problem of CPR administration;

e) the problem of potential AED malfunction;

f) the aggravation of problems (b) through (e) in the event that theuser of the AED is untrained or inadequately trained; and

g) the potential aggravation of any of problems (b) through (f) by theabsence of a highly experienced professional taking charge of theemergency scene.

The seven classes of problems (a) through (g) will now be addressed anddiscussed in detail.

First, an AED relies on its internal artificial intelligence to make adecision about whether to provide a proper high voltage response fortermination of a life threatening heart rhythm. The device must beprogrammed to anticipate as many situations as possible, and it must beprogrammed to function appropriately during each of those situations, inorder for the automated response to have the intended effect ofresuscitating the cardiac victim. The use of the device thus decouplesthe victim's treatment from the intelligence and judgment of a medicalprofessional who normally administers external defibrillation. Thisusurpation of the medical professional's role by a machine and itsminimally trained or untrained operator may, at times, result inincorrect or delayed responses in just those critical moments which canmake the difference between life and death.

AEDs, no matter how complex their algorithms are or will become, are notable to perform properly under conditions which are not explicitlyaddressed by their algorithms. For example, Kanz et al. (Circulation1999; Vol. 100: Abstract 1641, Page I-313) showed that AED-based rhythmdiagnosis was often incorrect in the setting of substantial externalelectromagnetic interference. When 12 units were evaluated in railwaystations, sensitivity ranged from 80 to 100%, and specificity rangedfrom 38 to 100%. In power stations, the performance was even worse, withboth sensitivity and specificity ranging from 0 to 100%.

Other important issues which may not be addressed by an algorithminclude the management of the victim who is fully or partially consciouswith a tachycardia, and the management of a victim with an implantablecardioverter-defibrillator or ICD. Still other issues beyond the scopeof current algorithms involve advanced management considerations such aspost-defibrillation treatment.

Sophisticated EMTs will not benefit by carrying AEDs since they would belikely to know far more than the information on which an AED algorithmis based. However, a defibrillator device which provides the EMT with animmediately available medical expert consultant could improve arrestoutcome.

The second limitation of AEDs relates to electrode positioning. It isknown that correct defibrillator pad positioning and application is veryimportant for successful defibrillation. Errors in positioning and poorelectrical contact are not uncommon among inexperienced operators. AEDsdo not actively guide the user in appropriate pad placement andapplication (other than by the provision of a diagram). Nor can theydetect or correct for inappropriate positioning and application, once ithas occurred. A defibrillator device which could provide such guidancewould be highly desirable. Although highly sophisticated electronicmeans could provide such guidance, a human observer with means forobserving pad placement could easily accomplish this.

Third, even partially trained AED users can not be expected to match theskills of a highly trained medical professional. For example, the casinostudy showed that 0.9 minutes elapsed from the time of defibrillatorattachment until the time of first shock. A medical professional couldaccomplish this action in a fraction of this time. A defibrillatordevice which lets a remote ultra-sophisticated medical professionaldeliver the shock would therefore save time, when compared with thecasino scenario.

Fourth, an AED does not coach an untrained bystander in the performanceof CPR. Although CPR is not required in arrests of short duration, theneed for it increases as the arrest duration increases. CPR wasadministered to some patients in the Minnesota study and in the casinostudy. The improved results in Boston were concomitant with not only anincrease in available AEDs but with firefighter CPR training as well.Ewy, in discussing successes with a limited form of CPR which involveschest compression without ventilation, points out that rapiddefibrillation and bystander initiated CPR are the major determinants ofsurvival of a VF arrest (New England Journal of Medicine 2000; Vol. 342:Pgs. 1599-1560). A defibrillator device which could provide CPRinstruction and guidance would be very advantageous. Althoughinstruction prior to CPR could be automated, the processes of guidanceduring CPR and of suggesting corrective maneuvers during CPR, are farmore easily accomplished by a human coach than by an algorithmic one.

Fifth, occasional malfunction of any electrical device is inevitable.Sweeny (cited above) noted seven instances of apparent AED malfunctionout of 260 uses. It is far more likely that a medical professional who(i) has expert knowledge of a sophisticated defibrillator device and itsbackup systems, and (ii) constantly monitors the functioning of thedefibrillator device during its operation, would be able to work arounda device malfunction. (In the Sweeney study, use of AEDs in a Charlotte,N.C. EMS program did not result in outcome improvement.)

Sixth, in each of the reports cited herein, in which AEDs were used,their use was by a trained operator. It is inevitable that an untraineduser will perform less accurately and take more time to do so. However,given that: (i) the ideal response time after an arrest would be evenless than that during the casino study (in which victims wereessentially under constant observation), and that (ii) the police orfire department response time is unlikely to ever be shorter than thecasino response time; then the only likelihood of achieving therequisite ultra-short response time is by having a device that can beused by an entirely untrained bystander. Such a device would have to bemore user-friendly than an AED. Such a device would have to be capableof both: (i) defibrillation, and (ii) closely linking an untrainedbystander with an expert medical professional who could guide himthrough every aspect of the resuscitation process. AEDs do not meet thisrequirement. Indeed, the AEDs which have been installed to datetypically display a warning to the potential user that the device isintended for use by trained personnel only.

Finally, since the aforementioned ideal external defibrillator devicewill require some level of participation by a human enabler (that is, anon-medically trained person who is available to use the device todefibrillate a victim of cardiac arrest), the creation of an environmentin which the enabler functions optimally is critical. AEDs cannotaddress the anxiety or reluctance of an individual operator and may, infact contribute to these. The cumulative effect of such feelings among agroup of bystanders, may contribute to the chaos and pandemonium whichnot infrequently accompany a cardiac arrest. On the other hand, thevoice of an experienced medical professional, taking charge, providinginstructions, and making decisions, is often a great source ofreassurance and stability, giving the assurance of proper conduct. AEDscannot provide this human element.

Clearly, once a patient has suffered and survived an initial,lifethreatening cardiac event, that patient must be monitored closely sothat the proper treatment may be brought to bear on an emergency basis.The U.S. Pat. No. 5,544,661 to Davis et al. discloses a patientmonitoring system which includes a portable device, attached to apatient, and a central station. The portable device includes an ECG anda photo-plethysmograph connected to the patient, and an arrhythmiaanalysis circuit which includes an expert system for determining whetherpre-established critical parameters have been exceeded. The portabledevice also includes a wireless wide area communication circuit forautomatically contacting the central station via a public cellulartelephone network when the expert system determines that assistance isneeded. When the central station is contacted, the patient's ECGwaveforms, measurements and trends are sent to the central monitoringstation and a two-way voice channel between the patient and the centralstation is automatically opened. The central station includes acomputerized facility from which a clinician can observe both the realtime data being sent from the patient and the patient's historicalrecords. The clinician can talk to the patient through the two-way voicechannel and can also activate therapeutic devices attached to thepatient such as an external defibrillator, a pacer or an automatic druginfusion device.

Similarly, the U.S. Pat. No. 5,564,429 to Born et al. discloses acardiorespiratory alert system which comprises a patient unit, a basestation and a remote unit. In a hospital configuration, several patientunits can communicate with the base station, which is located centrally,for example at a nurse's station. In a home configuration, the basestation can reside near the patient's bedside. In both cases, thecommunication between the patient unit and the base station is by way ofradio telemetry. The base stations are designed to communicate with aremote unit, either by radio telemetry or by use of commercial telephonelines.

The system provides alerts to the remote unit when life-threateningconditions are detected in a patient, yet it is tolerant to the presenceof artifact so that false positive alerts are reduced.

Upon sensing a life-threatening condition, a “caregiver”, who staffs theremote unit or “dispatcher station”, may remotely activate variousdevices, including an external defibrillator, pacer and drug infusiondevice, and/or may contact an EMS unit in the patient's immediatelocale, in an attempt to save the patient's life.

The subject matter of both the U.S. Pat. No. 5,544,661 and U.S. Pat. No.5,564,429 is incorporated herein by reference.

The systems disclosed in these two patents require that the portablepatient unit be worn at all times so that ECG and other patient criticalinformation can be continuously monitored. These systems cannot be usedin a normal emergency situation where a patient has no advance warningof a cardiac event and is therefore neither prepared nor monitored by alifesaving system. The U.S. Pat. No. 5,184,620 discloses a method ofmonitoring a patient's cardiac activity using a so-called “electrodepad” having a plurality of electrode sites which, upon placement againstthe patient's chest wall, provide ECG signals for determining if cardiacpacing and/or defibrillation is required.

Certain combinations of electrodes provide the path for pacing signalswhereas other combinations provide a path for defibrillation current.

The U.S. Pat. Nos. 5,593,426 and 5,782,878 (which have a similardisclosure) disclose a “communicator” for connecting each of a pluralityof automatic external defibrillators (“AEDs”) to a central communicationstation. The central station receives information from an AED, such aspatient ECG data and defibrillator operation data, and transmitsinformation, such as use instructions for a bystander, to this AED.

The U.S. Pat. No. 4,102,332 describes a portable defibrillator, with apreprogrammed dialer, that telephones a physician when activated by apatient. While the physician and patient communicate with each other viathe defibrillator's communication system, the physician can control theoperation of the defibrillator from his or her remote location. Duringuse, the defibrillator sends operation and status data to the physician.

The U.S. Pat. No. 6,141,584 discloses an automatic externaldefibrillator (AED) which is capable of storing ECG data anddefibrillator data and “handing off” this data, via an infra-red link,to equipment of emergency medical personnel when they arrive on thescene of a cardiac arrest.

The U.S. Pat. No. 6,148,233 discloses a wearable automatic externaldefibrillator; that is, a defibrillator which is worn by a patienthaving one or more contact electrodes attached to the chest wall of thepatient for transmitting defibrillation energy to the patient and forreceiving ECG information from the patient. This patent is directedspecifically to the contact electrode(s) which can be worn by a patientfor a relatively long time without skin irritation or damage. Thissystem is designed for patients who have previously experienced cardiacarrhythmias but are, perhaps, not ready for an implanteddefibrillator/pacer.

Finally, there are numerous patents which relate to ICDs. Such devices,which are also a form of automatic defibrillator, are in constantelectrical communication with the human heart. When implanted, such ICDsoperate independently, without external controls, to treat ventricularfibrillation (VF), ventricular tachycardia (VT) and supraventriculararrhythmias by applying one or more voltage pulses to the heart.

In their formal definitions, cardioversion refers to the delivery of ashock which is synchronized to the heart's electrical activity anddefibrillation refers to an asynchronous shock. For simplification,unless otherwise noted, either one of the terms cardioversion anddefibrillation shall hereinafter be referred to as simplydefibrillation, and either one of the terms cardiovertor anddefibrillator shall hereinafter be referred to as simply defibrillator.Such simplification is not intended to narrow the scope of the inventiondescribed herein, but is merely for the purpose of avoiding repeated useof the respective lengthy and rather awkward medical terminology.

SUMMARY OF THE INVENTION

It is a principal object of the present invention to provide theservices and superior ability of a highly-skilled medical professional(as compared to a fully automated apparatus) for diagnosing and treatingcardiac arrest or any other cardiac rhythm abnormality. As usedhereinafter, the term cardiac arrest is intended to include, and shallinclude, all types of cardiac rhythm abnormality.

It is a further object of the present invention to provide a systemwhich can markedly decrease the response time of a medical professionalto a cardiac arrest by facilitating lifesaving electrical therapy to theheart before the arrival of an emergency medical service or any othertrained personnel.

It is a further object of the present invention to provide a system forresuscitation after the onset of cardiac arrest which affords: a) adegree of communication redundancy; b) a network of backup systems; andc) a certainty of execution of operator commands which are required forpractical operation of the system by a remote medical professional.

It is a further object of the present invention to provide a system forresuscitation after the onset of cardiac arrest which can operatecompletely automatically in the event of a telecommunication breakdownor other fault which prevents a medical professional from using his orher judgment to control the operation of a defibrillator and/or pacingunit.

It is a further object of the present invention to allow a skilledmedical professional to remotely monitor and manage a cardiac arrestwhich may occur at one of a plurality of remote sites, thus alleviatingthe anxiety and avoiding the pandemonium which often accompany thetypical cardiac event. This skilled medical professional would be ableto maintain a standard of care that an untrained or minimally trainedAED user could not.

It is a further object of the present invention to provide a UniversalPad which may be used to apply multiple cardiac monitoring, pacing anddefibrillation electrodes to the chest wall of a cardiac victim.

These objects, as well as further objects which will become apparentfrom the discussion that follows, are achieved, in accordance with thepresent invention, by providing a cardiac monitoring and externaldefibrillation system which comprises a central station and a pluralityof remote, emergency site portable units, and a means for the centralstation to communicate with and control the remote site portable units.Once a remote site portable unit is attached to a victim of a cardiacarrest, the central station is capable of displaying selected items ofreal-time cardiac information for a human operator, in particular amedical professional, and issuing control signals, at the command of themedical professional, for controlling the application of defibrillationpulses to the victim. Prior to and after defibrillation pulses areapplied, cardiac and possibly respiratory information is received fromthe cardiac victim at the remote site for evaluation by the medicalprofessional. This information and information documenting all actionstaken by the medical professional is automatically stored for subsequentdownload to an emergency medical team (EMT), a hospital, or othermedical facility which eventually becomes responsible for care andtreatment of the victim. Throughout the process of emergency care, themedical professional can communicate by voice and/or video and/ordisplayed text to instruct the emergency site enabler and to receiveinformation from the enabler about the victim.

In particular, each of the plurality of remote sites is provided with anemergency cardiac monitoring and external defibrillation apparatus inthe form of a portable unit. This apparatus includes a variety of meansto apply contact electrodes to the chest wall of the cardiac victim. Onesuch means is a Universal Pad; that is, a semi-rigid, flexible pad,adapted to be placed on the chest wall of a cardiac victim, whichincorporates a plurality of cardiac contact electrodes at suitablepositions for monitoring ECG signals and applying defibrillation and/orpacing pulses to the victim.

The portable unit at the remote site also includes atransmitting/receiving device for sending cardiac and respiratoryinformation to, and receiving control signals from, the central stationand for sending and receiving voice, text and video.

The remote site portable unit also includes a defibrillator circuit,connected to the contact electrodes for applying high voltagedefibrillation pulses to these electrodes in response to defibrillationcontrol signals received from the central station. The remote siteapparatus may include a cardiac pacing circuit, connected to the contactelectrodes for applying lower voltage cardiac pacing pulses to theseelectrodes in response to pacing control signals received from thecentral station.

The cardiac monitoring and external defibrillator system, according tothe invention, provides and incorporates a number of advantageousfeatures. These include:

Enabling the medical professional at the central station to decidewhether the situation merits use of the emergency apparatus at theremote site;

Enabling the medical professional to summon the local emergency medicalservice (i.e. by contacting the “911” emergency service in the locale ofthe remote site);

Enabling the medical professional to direct the initial application ofthe Universal Pad and/or other contact electrodes on the victim's body;

Enabling the medical professional to direct a subsequent application ofthe Universal Pad and/or other contact electrodes when the initialtherapy did not succeed for any reason; for example, due to incorrectplacement of the electrodes or due to anatomic or other considerations.

Enabling the medical professional to compensate for less than perfectorientation of the electrodes applied to the victim's chest wall withoutreapplying the Universal Pad;

Enabling the medical professional to view the victim's ECG and make arhythm diagnosis whose accuracy can exceed the best algorithm of fullyautomated defibrillation equipment;

Enabling the medical professional to make a determination as to whetherany one or more of the contact electrodes are making poor contact withthe victim's chest wall, and to compensate for such poor contact;

Enabling the medical professional to defibrillate along differentspatial axes, and/or different points on the victim's body, therebyincreasing the chance of a successful outcome during a cardiac arrest;

Enabling the medical professional to deliver alternate therapiesincluding pacing;

Enabling the medical professional to decide whether high energy shock,low energy shock, pacing and/or CPR, or perhaps no therapy at all, isappropriate;

Enabling the medical professional to control multiple parameters ofelectrical therapy including voltage, pulse width, pulse shape, pulseenergy and timing;

Enabling the medical professional to instruct the enabler in the properCPR technique;

Enabling the medical professional to monitor and, if necessary, correctthe enabler in the proper performance of cardiopulmonary resuscitation(CPR);

Enabling the medical professional to assess the victim's respiratory andblood pressure status;

Enabling a single medical professional to supervise a plurality ofenablers at different cardiac arrest scenes;

Enabling a medical professional to triage the supervision ofsimultaneously occurring cardiac arrests to other medical professionals;

Enabling the medical professional to avoid chaos, panic, inaction,delayed action or inappropriate action by allowing this medicalprofessional to supervise emergency scene enablers;

Enabling the medical professional to release a lock holding the portableunit to a wall or to another stationary object, or to a wall-mountedstationary unit at the remote site of the cardiac arrest;

Enabling the medical professional to see a victim of cardiac arrest, anenabler at the scene, the placement of cardiac electrodes on thevictim's chest as well as the administration of CPR;

Enabling the medical professional at the central station, and/or thesystem itself, to diagnose a failing component or group of components ofthe system and to bypass or provide a substitute for these components;

Enabling the medical professional at the central station, or the systemitself, to assess the existence and/or maintenance of propercommunication between the central station and the remote site of thecardiac arrest and to remediate any problem by switching a communicationchannel, route or modality in any segment of the communication links;

Enabling the medical professional to utilize communication modalitiesother than voice, such as text and/or video; Enabling the medicalprofessional to receive a confirmation signal that a command, such as acommand to defibrillate with a specific shock energy and with specificcardiac electrodes, was duly executed;

Enabling the medical professional to receive error signals indicatingthat a command was not properly executed or that either the remoteequipment or the central station has malfunctioned;

Enabling the medical professional, and/or the system itself, to switchto an AED backup if necessary;

Enabling the medical professional, and/or the system itself, to transfercontrol of the portable unit to an emergency medical team, if necessaryand if appropriate;

Enabling the medical professional to properly identify emergency medicalpersonnel, before transferring control of the portable unit to suchpersonnel;

Enabling the medical professional to properly brief emergency medicalpersonnel on events which transpired before their arrival at the sceneof the emergency;

Enabling the medical professional to assist emergency medical personnelduring and after a cardiac arrest by accessing databases which maycontain information about the victim and/or his medications and/or hisimplanted pacemaker or defibrillator (if any);

Enabling the medical professional to assist emergency medical personnelduring and after a cardiac arrest by monitoring the victim's cardiac andrespiratory status;

Enabling the medical professional to assist emergency medical personnelduring and after a cardiac arrest by providing advice and guidanceconcerning the medical management of the victim;

Enabling the medical professional to assist emergency medical personnelduring and after a cardiac arrest by providing advice and guidanceconcerning the operation of the portable unit;

Enabling the medical professional or other trained personnel tosupervise the reattachment of the portable unit to the wall or to thestationary unit or its return to the position in which it was locatedprior to the cardiac arrest;

Enabling the medical professional or other trained personnel tosupervise the restocking of the portable unit;

Enabling the medical professional or other trained personnel to visuallyinspect the portable and stationary units;

Enabling the medical professional or other trained personnel to assessthe electrical and mechanical functioning of the portable and stationaryunits;

Enabling the medical professional to maintain a complete, secure,encrypted record of the events and data related to a cardiac arrest;

Enabling the medical professional to transmit information concerning thearrest in a secure, encrypted manner, in accordance with local andfederal statutes and regulations;

Enabling the medical professional to control the function of animplanted medical device;

Enabling the medical professional to work with a foreign languagespeaking enabler via an interpreter, or a computer program whichperforms such function; and

Enabling the medical professional to deal with a potential prankster orvandal by visually identifying such individual.

According to a particular feature of the invention, the emergencycardiac monitoring and external defibrillation apparatus, which isdisposed at each of a plurality of remote sites, is divided into twoseparate units:

(1) a stationary unit, adapted for permanent installation at the remotesite, which is capable of communicating with the central station and hasa transmitting/receiving device for electronic communication with aportable unit; and

(2) a portable unit, releasably attached to the stationary unit, whichhas a transmitting/receiving device for electronic communication withthe stationary unit.

The portable unit and the stationary unit are joined together by areleasable lock which is controlled from the central station by aportable unit release signal. When the medical professional determinesthat an enabler should take the portable unit to the side of a cardiacvictim, he may generate and transmit the portable unit release signal.

Advantageously, the portable unit is provided with a sensor for sensingwhen it has been released from attachment to the stationary unit. Theportable unit is preferably also provided with a sensor to sense whenthe portable unit has been placed on the floor next to a victim with aproper orientation of the unit (i.e., with the proper side up).

According to a particular feature of the present invention, thestationary unit comprises a battery charger and the portable unitcomprises a battery for powering the electronic circuits therein. Whenthe portable unit is attached to the stationary unit, the batterycharger maintains the battery in a charged condition. The stationaryunit may also be provided with a battery backup to safeguard against apower failure.

To initiate the operation and to alert the medical professional, theportable unit is preferably provided with a button, to be pressed bysomeone (e.g., a bystander) in the vicinity of the victim, in the caseof a medical emergency. This button may, for example, have a large redcross and/or the words “MEDICAL EMERGENCY” imprinted thereon. The personwho presses this button, and then becomes an “enabler”, facilitates or“enables” the resuscitation of the victim under the direction of themedical professional. Pressing the button initiates the communicationprocess between the enabler and the medical professional.

Although the preferred communication modality is from portable unit toand from stationary unit by radio frequency, and from central station toand from the stationary unit via public access telephone company landline, the medical professional or the system can, if desirable, selectan alternate route. Examples of such selections would include using aradio frequency link between the central station and the stationaryunit, or bypassing the stationary unit, with a link from the portableunit to the central station. Furthermore, although the public telephonenetwork may be used, a private network or the Internet could also beused.

In a preferred embodiment the system initially establishes properfunction of the communication components, which link the central stationand the portable unit during the first step or layer of a handshakeroutine. A series of such handshakes occurs, each incorporating theprevious one and each encompassing a larger circle of sub-systems, untilthere is complete informational exchange between the medicalprofessional and the enabler. Such handshakes are utilized throughoutthe duration of the cardiac arrest to ensure robust and reliablecommunication between the medical professional and each of the enabler,the victim (in which case the communication consists of an electricallink) and the emergency medical team. Each handshake is rendered leastlikely to fail by the availability of multiple levels of backup systems

Once the basic communication handshake has been effected, the properfunctioning of the next layer of components is quickly confirmed. Thislayer includes the ability of the system to send and receive voice anddata in each direction, the ability of the medical professional toproperly transmit commands, and the proper receipt of the commands bythe portable unit. Diagnostic features within the system allow for theidentification of and substitution for a failing sub-system or sub-unitwithin either the central station, the stationary unit or the portableunit. Such identification and substitution may be performed with orwithout the active participation of the medical professional.

Thereafter, according to a particular feature of the present invention,the handshaking is extended to include actual communication between themedical professional and the enabler. In particular, the medicalprofessional will attempt to verbally communicate with the enabler inthe local language.

According to a preferred feature of the invention, at least voicecommunication is made available between the portable unit and thecentral station. Advantageously, the words spoken by the medicalprofessional are displayed as text on the portable unit so that theenabler may see as well as hear the instructions given. A video link isalso desirable and, in accordance with a preferred feature of theinvention, the medical professional at the central station is providedwith a device for remotely controlling the orientation of a video cameraon the portable unit, so that the medical professional may best see theenabler, the victim and even the portable unit itself. To facilitatehands-free voice communication with the enabler at the remote site, theportable unit is preferably provided with a microphone and loudspeaker,and with a headset which contains earphone and microphone.

In the event that proper communication between the medical professionaland the enabler can not be established and/or maintained, backup AEDfunction is available. The portable unit will select the AED function ifeither the initial handshake fails, or if there are either substantialinterruptions to, or degradation of a previously establishedcommunications link. AED control can also be selected by the medicalprofessional if he deems the quality of the communications link to beinadequate.

The medical professional may continue to monitor an event even thoughcontrol may have been handed over to the AED. If the medicalprofessional later finds that robust communication has beenre-established, he may resume and take control back from the AED. Insuch a case, the medical professional would be able to securely downloadthe encrypted information pertaining to any gap in the data/eventsequence, from the data storage unit within the portable unit.

A master control unit within the portable unit selects which person, orwhich circuitry controls the executive functioning of the portable unit.When communication with the central station is established, the mastercontrol unit lets the medical professional control executivefunctioning. A communications failure results in the AED having control.When one or more members of an emergency medical team is/are present,the master control unit is designed to give this team the opportunity tocontrol the portable unit. Yet another function of the master controlunit is to allow a remote person to perform diagnostic testing andinformation exchange with the portable unit.

Following the initial establishment of communication between the medicalprofessional and the enabler, the medical professional may ask theenabler for a description of the event and may thereby decide whetherrelease of the portable unit from the stationary unit is appropriate.Thereafter, if and when the portable unit is released, the enabler maybe directed to carry the unit to the victim's side.

At this point the medical professional may instruct the enabler as tothe proper selection, positioning and application of the contactelectrodes and/or the Universal Pad.

Once the electrodes have been applied, the medical professional willbegin to receive and review ECG data from the victim. Based on thisinformation the medical professional will use his judgment to decideupon the proper initial therapy. For example, the medical professionalmay decide to apply a defibrillation pulse of a particular energy andwaveform through a particular combination of electrodes. Alternatively,the medical professional may decide that pacing is a more appropriatetherapy or that no electrical therapy is needed.

After the administration of the initial electrical therapy the medicalprofessional will reassess the condition of the victim, by using thetransmitted ECG and other transmitted data, and decide upon the nextstep.

In particular, if the first therapy was either unsuccessful, partiallysuccessful or transiently successful, the medical professional may electto either repeat the identical therapy or to modify it, eitherqualitatively or quantitatively. For example, if a 100 joule shockapplied between one particular pair of electrodes (e.g., specific onesof the electrodes on the Universal Pad) was unsuccessful, the medicalprofessional might then elect to apply a 150 joule shock between adifferent combination of two or more electrodes on the Universal Pad.

In order for a medical professional to properly and safely administerremote therapy during an emergency situation, he needs to receivereliable confirmation that each command: a) was properly sent from thecentral station; b) was properly received at the remote site; and c) wasproperly executed. With a confirmation system in place, if a command fora particular therapy is not followed by the restoration of a normalrhythm, the medical professional can conclude that the therapy itselffailed; rather than having to consider the possibility that treatmentfailure may have resulted from a failure of the system to actuallyrender the medical professional-directed treatment.

Cardiopulmonary resuscitation (CPR) can substantially improve theoutcome of certain cardiac arrests, especially if electrical therapydoes not rapidly restore normal cardiopulmonary function. If and whenthe medical professional feels that CPR is a desirable adjunct toelectrical therapy, he may instruct or coach the enabler in proper CPRtechnique. The instruction may be via video and/or audio transmissionfrom the central station to the portable unit during the arrest.

At the time that the portable unit is released, the cardiac monitoringsystem according to the invention may automatically contact the localemergency unit. When such emergency personnel arrive, the medicalprofessional can hand off some or all responsibility to the on-sceneemergency medical team (EMT), after the EMT has been properlyidentified.

For this to occur, the medical professional would issue a command to themaster control circuit. This would convert the portable unit into amanually controlled device. The medical professional could then continueto observe and advise in such a situation.

In addition to monitoring ECG signals from the victim, the portable unitmay be provided with a blood pressure measuring device (e.g., anautomatic cuff for measuring systolic and diastolic pressure of thevictim); and/or a pulse oximetry monitoring device for measuring theblood oxygen content of the victim.

As used herein, the term “pulse oximetry” is intended to include themeasurement of any blood gases (oxygen, carbon dioxide and the like),blood pH, blood sugar or any other blood component.

According to a further aspect of the invention, the Universal Pad is amulti-electrode pad which includes five defibrillator electrodesarranged in two separate rows with two electrodes in a first, upper rowand three electrodes in a separate, lower row. These electrodes may beused in combinations of two or more for defibrillation, pacing and/orECG recording. Advantageously, a plurality of ECG electrodes, which aresmaller than the defibrillator electrodes, are distributed adjacent tothe five defibrillator electrodes; These electrodes may be used incombinations of two or more for ECG recording. Alternatively, ECGrecording may be accomplished using a mixture of defibrillatorelectrodes and ECG electrodes.

In another embodiment of the Universal Pad, the electrodes are arrangedin a matrix of many separated electrodes. This gives the medicalprofessional additional flexibility in selecting combinations of two ormore electrodes to which defibrillation and/or pacing pulses are to beapplied and from which ECG signals are to be received.

Other arrangements of contact electrodes, adapted for application to thevictim's body, may also be used. For example, the portable unit may beoperated with two or more standard individual contact electrodes forreceiving ECG signals and applying defibrillation and/or pacing pulses.

According to a particular feature of the present invention, theUniversal Pad, or any of the contact pads, may be provided with aprotective and insulating backing that is peeled off prior to use. Meansare provided to signal to the medical professional at the centralstation when the backing is peeled off. When the backing is peeled off,the medical professional is informed as to which electrode pad, fromamong a variety of pads with different electrode configurations, isactually being used by the enabler.

According to a particular feature of the invention, the male and femaleversions of the cable connectors which link the electrode pads with theportable unit, hereinafter referred to as Universal Connectors, allow anumber of advantageous features. These include: a) the ability to attachany of a variety of electrode pads which terminate in a female UniversalConnector, to any male Universal Connector of the portable unit; b) theability of the medical professional to know which (if any) particularvariety of pad is attached to each of the portable unit UniversalConnectors; and c) the ability of the medical professional to know whenthe backing material has been removed from an electrode pad.

According to a particular feature of the invention, a video system isprovided which serves the following functions:

a) If one way video is provided from the portable unit to the centralstation:

-   -   (i) It lets the medical professional view an incorrect pad        orientation and advise the enabler to correct it.    -   (ii) It lets the medical professional directly visualize the        victim for diagnostic and management purposes: state of        consciousness, presence of seizure activity, head positioning.    -   (iii) It allows the medical professional to give advice        concerning CPR technique.    -   (iv) It is useful for ruling out a prankster, in the event that        initial button press is followed by absent, inadequate or        inappropriate verbal response from a potential enabler.    -   (v) During a system diagnostic check, the video camera may be        oriented to inspect the physical integrity of the portable and        stationary units.    -   b) If two way video is provided between the portable unit and        the central station:    -   (i) It allows the medical professional to illustrate proper        defibrillator pad positioning and orientation. The correct        position and orientation could be shown as a cartoon or virtual        image superimposed on the actual image of the victim.    -   (ii) It allows detailed illustration of CPR technique. This too        could be superimposed or overlaid onto the actual image of the        victim.    -   (iii) It can help the medical professional to identify various        components of the system to the enabler by displaying them.    -   (iv) It can help the medical professional to instruct the        enabler as to the application of blood pressure measuring, pulse        oximetry and ancillary paraphernalia included in the tool-kit of        the portable unit.    -   (v) An image of the medical professional may have a reassuring        effect upon the enabler and upon other bystanders.

In another preferred embodiment of the present invention, the medicalprofessional may guide a person who is returning the previously usedportable unit to the location in which it is intended to remain when notin use. Such guidance may include: a) information about replacing andrestocking components of the portable unit tool-kit; b) informationabout the location to which the portable unit must be returned; and c)positioning and orienting information to allow the portable unit to beproperly attached to a stationary unit or stationary lock.

In another preferred embodiment of the invention a global positioningsystem within the portable unit may allow the medical professional toknow the location of any such portable unit. This would facilitate themedical professional's ability to keep track of the location of eachportable unit, especially if it has been transported to a substantiallydifferent location during or after its use. It would also let themedical professional ascertain the location of an en-route EMT, if theEMT was transporting a portable unit which was equipped with a globalpositioning system.

In another preferred embodiment of the present invention, the centralstation and/or the emergency defibrillation apparatus disposed at theremote sites include a storage device which stores the ECG signals andpossibly other data received from the victim and the control and othersignals transmitted from the central station. In addition, the voice,text and video communications may be stored for later review. In thisway, a cardiac arrest “event” can be analyzed and reviewed for laterinstructional, medical and legal purposes. Such storage, review andanalysis would be in compliance with pertinent local and federalstatutes and regulations.

A still further advantageous feature of the present invention includesproviding means at the portable unit (such as a keyboard, real orvirtual) to permit communication with the central station by text, inthe event of breakdown in voice communication. As already mentionedabove, the instructions of the medical professional at the centralstation, which are normally transmitted by voice, can be displayed intext at the portable unit. Another alternative communications interfacewith the enabler would include portable unit or central stationinitiated voice prompts and/or speech recognition.

According to a particular, advantageous feature of the presentinvention, means are provided at the portable unit to transmit controlsignals to and receive data signals from an ICD or a pacemaker, whichhas been previously implanted in the victim's chest. In this way, amedical professional may attend to the emergency medical needs of thistype of victim as well. In this case, the contact electrodes whichreceive ECG signals and which transmit defibrillator and/or pacingpulses to the heart have already been implanted, thus eliminating theneed for an enabler to place any contact electrodes on the victim'schest.

According to a particular feature of the invention, communicationbetween the portable unit and the central station may traverse a routein which there may be more than one stationary unit and/or one or moreadditional portable units, with each of said stationary units and saidadditional portable units functioning as a repeater, i.e. as acommunications relay.

Finally, it is contemplated that in a large, extensive system with manyportable units at various remote sites more than one cardiac arrest mayoccur simultaneously. Accordingly, the invention provides means for: a)a single medical professional supervising multiple simultaneous arrests;b) one central station with multiple attendant medical professionals anda means for triaging the supervision of cardiac arrests among them; andc) a network of central stations, each with one or more attendantmedical professionals, and a means for triaging the supervision ofcardiac arrests among them.

For a full understanding of the present invention, reference should nowbe made to the following detailed description of the preferredembodiments of the invention as illustrated in the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a representational diagram of the scene of a medical emergencyand of a central station, each equipped with the resuscitation systemaccording to the present invention.

FIG. 2A is a perspective view showing a typical medical emergencysituation in which a victim lies on the floor and a bystander becomes anenabler by activating the cardiac monitoring and defibrillation systemaccording to the present invention.

FIG. 2B is a perspective view showing a typical medical emergencysituation in which a victim lies on the floor and an “enabler” utilizesthe cardiac monitoring and external defibrillation system according tothe present invention.

FIG. 3 is a representational diagram of the various display screens andcontrol devices at the central station in the cardiac monitoring andexternal defibrillation system according to the present invention.

FIG. 4A is a block diagram of the cardiac resuscitation system, withouta stationary unit, in overview.

FIG. 4B is a block diagram of the cardiac resuscitation system, with astationary unit, in overview.

FIG. 5A is a front elevational view of a preferred embodiment of a“Universal Pad” which may be used with the cardiac monitoring andexternal defibrillation system according to the present invention toapply contact electrodes to the chest wall of a victim.

FIG. 5B is a front elevational view of an alternative embodiment of aUniversal Pad according to the present invention.

FIG. 5C is a front elevational view of a second alternative embodimentof a Universal Pad according to the present invention.

FIG. 5D is a rear elevational view of the Universal Pad according to thepresent invention showing a peel-off backing covering the contactelectrodes.

FIG. 5E is a side elevational view of the Universal Pad showing the padsubstrate, the contact electrodes and the peel-off backing.

FIG. 5F is a front elevational view of still another alternativeembodiment of a Universal Pad having a large number of contactelectrodes.

FIG. 5G is a front elevational view of three single electrode pads, twoon a victim's chest, and one on his back.

FIG. 6A is a perspective view of the external configuration of awall-mounted device at a remote station of the cardiac monitoring andexternal defibrillation system according to the present invention.

FIG. 6B is a perspective view of the detachable portion (so-called“portable unit”) of the wall-mounted device of FIG. 6A.

FIG. 7A is a front elevational view of the equipment cabinet in theportable unit of FIG. 6B.

FIG. 7B is a representational diagram showing how the Universal Padsand/or contact electrodes, disposed in the portable unit, may beconnected.

FIG. 8 is a perspective view of the rear panel of the portable unit ofFIG. 6B.

FIG. 9 is a perspective view of the base portion (so-called “stationaryunit”) of the wall-mounted device at the remote station with theportable unit removed.

FIG. 10 illustrates preferred images which may appear on the two displayscreens of the portable unit.

FIG. 11 illustrates alternative preferred images which may appear on thetwo display screens of the portable unit.

FIG. 12 are a flow chart showing the communication handshake protocol atthe PU.

FIG. 13 are a flow chart showing the communication handshake protocol atthe CS.

FIG. 14 are a flow chart showing the data/commands handshake protocol atthe central station of the system according to the present invention.

FIG. 15 are a flow chart showing the audio handshake protocol betweenthe enabler and the medical professional located at the central stationof the system according to the present invention.

FIG. 16 comprises FIGS. 616A, 16B and 16C.

FIG. 16A is a flow chart showing the informational handshake protocolbetween the enabler and the medical professional located at the centralstation of the system according to the present invention.

FIGS. 16B and 16C, taken together, are a flow chart illustrating theprocess by which the medical professional releases the locking mechanismwhich attaches the portable unit to the stationary unit.

FIG. 17 is a flow diagram showing typical voice instructions of amedical professional offered during the transport of the portable unitfrom the stationary unit to the victim according to the presentinvention.

FIGS. 18A, 18B, 18C, 18D, 18E and 18F, taken together, are a flow chartshowing voice and video instructions offered by the medicalprofessional, and the medical professional's receipt of information andissuance of video control commands during the setup of the portable unitat the victim's side.

FIG. 19 is a flow diagram illustrating the medical professional'sprocess of heart rhythm analysis based on a victim's ECG during amedical emergency.

FIG. 20 is a flow chart of the medical professional's protocol fortreating ventricular fibrillation and ventricular tachycardia.

FIG. 21 is a table and flow chart illustrating the various possibletreatments when a victim's condition, based on information the medicalprofessional receives, is less severe than cardiac arrest.

FIG. 22 is a flow chart of the medical professional's protocol fortreating tachycardia with anti-tachycardia pacing.

FIG. 23 illustrates the protocol of a medical professional in the caseof bradyarrhythmia in a victim.

FIG. 24 is a flow diagram illustrating the confirmation protocol fortransmission of messages between the central station and a remotestation in the cardiac monitoring and external defibrillation systemaccording to the present invention.

FIG. 25 illustrates a touch-sensitive display screen at the centralstation for assessing and controlling communication with portable andstationary units at remote sites.

FIG. 26 illustrates a touch-sensitive display screen at the centralstation for controlling voice prompts at the portable unit.

FIG. 27 illustrates a touch-sensitive display screen at the centralstation for controlling deployment of the portable unit.

FIG. 28 illustrates a touch-sensitive display screen at the centralstation for controlling the video camera and video displays at theportable unit.

FIG. 29 illustrates a touch-sensitive display screen at the centralstation for initial assessment of pad contact and of ECG.

FIG. 30 illustrates a touch-sensitive display screen at the centralstation for selection of electrodes on the matrix electrode pad.

FIG. 31 illustrates a touch-sensitive display screen at the centralstation for selection of electrodes on the five electrode pad.

FIG. 32 illustrates a touch-sensitive display screen at the centralstation for selection of electrodes when multiple single electrode padsare used.

FIG. 33 illustrates a touch-sensitive display screen at the centralstation for selection of defibrillation electrodes, and control of thedefibrillation energy, waveform and synchronization.

FIG. 34 illustrates a touch-sensitive display screen at the centralstation for control of the on the defibrillator energy.

FIG. 35 is illustrates a touch-sensitive display screen at the centralstation for control of the defibrillator synchronization.

FIG. 36 is illustrates a touch-sensitive display screen at the centralstation for control of defibrillation and pacing pulse shape.

FIG. 37 is a diagram of the central station touch-sensitive displayscreen for controlling anti-tachycardia pacing.

FIG. 38 illustrates a touch-sensitive display screen at the centralstation for selection of pacing electrodes and for control of thecardiac pacing parameters and waveform.

FIG. 39 illustrates a touch-sensitive display screen at the centralstation for control of the cardiac pacing amplitude.

FIG. 40 illustrates a touch-sensitive display screen at the centralstation for control of the bradycardia pacing rate.

FIG. 41 illustrates a touch-sensitive display screen at the centralstation for the performance of diagnostic testing upon a portable and/orstationary unit at a remote location.

FIG. 42 illustrates a touch-sensitive display screen at the centralstation for controlling the triage of multiple medical emergencies amongmultiple medical professionals at multiple central stations.

FIG. 43 illustrates a touch-sensitive display screen at the centralstation for selection of screens to displayed on the central stationconsole.

FIG. 44 illustrates a touch-sensitive display screen at the centralstation for assessing confirmation and error signals.

FIG. 45 is a general block diagram of the electronic circuits employedat a remote station of the cardiac monitoring and externaldefibrillation system according to the present invention.

FIG. 46 is a detailed block diagram of the electronic circuits of theportable unit.

FIG. 47 is a detailed block diagram of the electronic circuits of thestationary unit.

FIG. 48 is a detailed block diagram of the electronic circuits of themaster control unit.

FIG. 49 is a block diagram of the electronic circuits of the centralstation.

FIG. 50 is a block diagram of the stationary unit decoder.

FIG. 51 is a block diagram of the portable unit decoder.

FIG. 52 is a block diagram of the portable unit encoder.

FIG. 53 is a block diagram of the central station decoder.

FIG. 54 is a block diagram of the central station encoder.

FIGS. 55A and 55B are flow charts showing the diagnostic checkingroutine for the portable unit.

FIGS. 56A, 56B, 56C, 56D, 56E and 56F illustrate possible connectorterminal arrangements for connecting a variety of Universal Pads andsingle electrode pads to the portable unit at a remote station.

FIG. 57 is a block diagram of a network of central stations.

FIG. 58 is a block diagram illustrating the multiplicity ofcommunication options between the portable unit and the stationary unit,and between the stationary unit and the central station.

FIG. 59 is a block diagram showing a repeater unit and multiplestationary units deployed among a portable unit and the central station.

FIG. 60 is a block diagram for communicating with and controlling animplantable cardioverter defibrillator.

FIG. 61 is a representational diagram showing the use of the systemaccording to the present invention to apply defibrillation pulses bymeans of two separate defibrillators.

FIG. 62 is a representational diagram showing the use of the systemaccording to the present invention to supply and monitor air to avictim.

FIG. 63 is a representational diagram showing the use of the systemaccording to the present invention to measure transthoracic impedance.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Contents 1. SystemOverview

1.1 Description of the Emergency Scene

1.2 Description of the Central Station

1.3 Block Diagram of the System

-   -   1.3.1 Two Unit System: Portable Unit and Central Station    -   1.3.1.1 System Operation when PU-CS Link is Intact    -   1.3.1.2 AED Backup in the Event of Communication Failure; Role        of the Master Control Unit    -   1.3.2 Three Unit System: Portable Unit, Stationary Unit and        Central Station

1.4 Figure Assignments

2. Portable Unit and Stationary Unit: Exterior Elements

2.1 Portable Unit: Front and Right Side Panels

2.2 Portable Unit: Tool-kit

2.3 Portable Unit: Rear and Left Side Panel

2.4 Stationary Unit: Front and Side Panels

2.5 Portable Unit: Screens

3. Electrode Pads

3.1 Physiology of Defibrillation

3.2 Torso-Shaped Multi-electrode Pads

3.3 Matrix Electrode Pad

3.4 Single Electrode Pads

4. Sample Cardiac Arrest and System Operation

4.1 Overview of Sample Arrest

-   -   4.1.1 Phase One: Initial Enabler Action    -   4.1.2 Phase Two: Handshakes Linking Enabler and MP    -   4.1.2.1 Role Played By Handshakes; Relationship Between        Handshakes and Backups; Relationship Between Handshakes and        Links    -   4.1.2.2 Backup Systems for a Failed Handshake    -   4.1.2.3 Four Handshakes which Link the Enabler and the MP    -   4.1.2.3.1 The Communication Handshake    -   4.1.2.3.2 The Data/Commands Handshake    -   4.1.2.3.3 The Audio Handshake    -   4.1.2.3.4 The Informational Handshake    -   4.1.2.4 Role of the Stationary Unit in the Handshake Protocol    -   4.1.2.4.1 Single Direct Link Between PU and CS as the Default        Routing Approach; Stationary Unit Functions as a Backup    -   4.1.2.4.1.1 Direct PU-CS Link Can Not Be Established; Failure of        One But Not Both Possible PU-SU Connections; Successful SU-CS        Connection    -   4.1.2.4.1.2 Direct PU-CS Link Can Not Be Established; Failure of        Both Possible PU-SU Connections and/or Failure of SU-CS        Connection    -   4.1.2.4.2 Two Connections: One from PU to SU and One from SU to        CS as the Default Routing Approach    -   4.1.2.4.2.1 Two-Segment Default; Initial PU-CS Link Successful    -   4.1.2.4.2.2 Two-Segment Default; Initial PU-CS Link Unsuccessful    -   4.1.2.4.3 Redundant Links, in which There is Both a Direct PU-CS        Link and an Indirect PU-SU-CS Link    -   4.1.2.4.4 More Elaborate Routes for the PU-CS Link    -   4.1.2.4.5 Depth of Handshake Layers    -   4.1.3 Phase Three: Transport of PU to Victim; Victim—MP        Handshake; PU Setup at Victim's Side    -   4.1.3.1 PU Release and Transport    -   4.1.3.2 Handshakes Linking Victim and MP    -   4.1.3.2.1 The Four Layer Victim—MP Link    -   4.1.3.2.2 Backup Systems for Failure in the Victim—MP Link    -   4.1.3.3 MP Commands, Confirmation Signals and Error Signals    -   4.1.3.4 Telemetry Signals    -   4.1.4 Emergency Medical Management of the Cardiac Arrest by the        Medical Professional    -   4.1.4.1 Defibrillation and Pacing by the MP    -   4.1.4.2 Other Actions Directed by the MP to Support Blood        Pressure    -   4.1.5 Phase Five: Management Immediately Post Electrical        Resuscitation    -   4.1.6 Phase Six: EMT Arrival, Transfer of Control of the PU from        MP to EMT    -   4.1.6.1 EMT Choices Other Than Assuming Control of the PU        Currently Attached to the Victim    -   4.1.6.2 Handshakes Linking EMT and MP    -   4.1.6.2.1 First and Second Layers of EMT-MP HS:

Password which Gives Control of PU to EMT, Rather Than Giving Control ofPU to AED/P

-   -   4.1.6.2.2 Third and Fourth Layers of EMT-MP HS    -   4.1.7 Management by the EMT, after Transfer of PU Control to the        EMT, by the MP    -   4.1.7.1 Transfer of PU Control    -   4.1.7.2 Briefing of EMT by MP    -   4.1.7.3 Method of PU Operation by the EMT    -   4.1.7.4 MP Role During EMT Use of the PU    -   4.1.7.4.1 Medical and Technical Support by the MP    -   4.1.7.4.2 Pharmacologic Support by the MP    -   4.1.8 MP Role After Victim Arrives at the Hospital

4.2 Sample Cardiac Arrest: Correspondence Between Events During theArrest, Flow Diagrams, Screens, Handshakes and Confirmation Signals

4.3 Role of the Medical Professional

-   -   4.3.1 Expert Decisions Made by the MP During the Cardiac Arrest    -   4.3.1.1 MP Decision to Change the Defibrillation Vector for the        Second Shock    -   4.3.1.2 MP Distinction Between Asystole and Ventricular        Fibrillation    -   4.3.1.3 MP Action to Improve Victim's Blood Pressure    -   4.3.1.4 Other MP Decisions Requiring Medical Expertise    -   4.3.2 Enabler Guidance by the MP    -   4.3.2.1 Enabler Guidance in Proper Application of the Electrode        Pad    -   4.3.2.2 Enabler Guidance in Cardiopulmonary Resuscitation    -   4.3.2.3 Enabler Guidance in Other Activities    -   4.3.3 EMT and Physician Guidance by the MP

4.4 Time Allocation During the Sample Cardiac Arrest

-   -   4.4.1 General Considerations Regarding Prediction of Duration    -   4.4.2 Enabler Travel Time    -   4.4.3 Duration of Other Enabler Tasks    -   4.4.4 Time Allocation for MP Tasks During Phase Four    -   4.4.5 Time Allocation Involving EMT Events    -   4.4.6 Correction for Simultaneous or Nearly Simultaneous Tasks        or Events

4.5 Further Details Concerning Specific Issues During the Sample CardiacArrest

-   -   4.5.1 Phase One: Amount of Time for Enabler to Reach PU    -   4.5.2 Specific Issues During Phase Two    -   4.5.2.1 Initial and Subsequent MP Screens    -   4.5.2.2 Facilitated Lock Release in the Event of Failure of        Handshake #1 or #2    -   4.5.3 Specific Issues During Phase Three    -   4.5.3.1 The MP Interface with Emergency Medical Services    -   4.5.3.2 Enabler Action During Transport of PU to Victim    -   4.5.3.3 MP Assessments and Actions, Upon Arrival of the PU at        the Victim's Side    -   4.5.3.4 Enabler Headset Handshake    -   4.5.4 Specific Issues During Phase Four    -   4.5.4.1 Wide Variety of MP Choices for Defibrillation and Pacing        Parameters; Central Station Screens which Correspond to these        Choices    -   4.5.4.2 MP Instructs Enabler in the Application of Blood        Pressure and Blood Oxygen Saturation Devices    -   4.5.5 Specific Issues During Phase Five    -   4.5.5.1 Possible Performance of CPR During Phase Five    -   4.5.5.2 Multiple Possible Types and Sources of Victim Related        Information    -   4.5.5.3 Multiple Possible Means of Tracking Local Emergency        Services    -   4.5.6 Specific Issues During Phase Six    -   4.5.6.1 Analogous Aspects of the Enabler-MP Link During Phase        Two, and the EMT-MP Link During Phase Six    -   4.5.6.2 Timing of EMT Arrival    -   4.5.6.2.1 Time Saved by Using the Invention: Estimation of the        Earliest Possible Defibrillation by EMT, Without the Invention    -   4.5.6.2.2 More Realistic Estimates for EMT Defibrillation    -   4.5.7 Specific Issues During Phase Seven    -   4.5.7.1 Overview of Phase Seven: Two Sequences of Events    -   4.5.7.1.1 Analogous Aspects of Phase Seven and Phase Three    -   4.5.7.1.2 Two vs. One Portable Unit at the Arrest Scene    -   4.5.7.2 Two Portable Units Available: New Versus Old PU as the        Replacement Unit    -   4.5.7.2.1 Option One: Old PU Remains Attached to the Victim; New        PU to be Attached to the Stationary Unit; Transportation of the        New PU to the SU    -   4.5.7.2.2 Option Two: New PU is Attached to the Victim; Old PU        to be Reattached to the Stationary Unit    -   4.5.7.3 Housekeeping Activities Before Returning the Old PU to        the SU; Transportation of the Old PU to the SU    -   4.5.7.3.1 MP Role During Housekeeping    -   4.5.7.3.2 Choice of Individual to Perform the Housekeeping        Activities    -   4.5.7.3.3 Electrode Pad Replacement; Oximetry Sensor Replacement    -   4.5.7.3.4 Replacement of Non-Disposable Items    -   4.5.7.3.5 Video Boom and Antenna Retraction Prior to Moving the        PU    -   4.5.7.3.6 Transportation of the Old PU to the SU    -   4.5.7.4 Attachment of the PU to the SU    -   4.5.7.4.1 Who Performs the Attachment?    -   4.5.7.4.2 Mechanical Issues in the Attachment Process    -   4.5.7.4.3 Endpoint for PU-SU Attachment    -   4.5.7.4.4 Checking the PU Post-Attachment    -   4.5.7.5 Choices in the Event of Communications Failure During        Phase Seven    -   4.5.7.5.1 EMT Communications Choices Using Only One Portable        Unit    -   4.5.7.5.2 EMT Communications Choices Using a Second Portable        Unit    -   4.5.7.5.2.1 Choice in which PU-2 is the Only PU which        Communicates with the Central Station    -   4.5.7.5.2.2 Choices in which Both PU-1 and PU-2 are Used in        Tandem; Even More Elaborate Links    -   4.5.7.6. Possible Need for Two Nearly Simultaneous MP        Conversations During Phase Seven    -   4.5.7.7 The Circumstance in which EMT Does Not Bring a        Replacement PU    -   4.5.7.7.1 Option Three: Sole PU Remains at the Arrest Scene    -   4.5.7.7.2 Option Four: Sole PU is to be Transported with the        Victim    -   4.5.7.8 Protocol Endpoints During Phase Seven    -   4.5.7.8.1 Definition of Victim Detachment from PU    -   4.5.7.8.2 Circumstances in which a PU Would Not Be Promptly        Replaced    -   4.5.7.8.2.1 PU Non-Replacement at the Arrest Site    -   4.5.7.8.2.2 Non-Replacement of the EMT PU

4.6 Post-Arrest Issues

-   -   4.6.1 On-Site Equipment Inspection and Assessment    -   4.6.1.1 Timing of the On-Site Visit    -   4.6.1.2 Items Assessed During the On-Site Evaluation Process    -   4.6.2 Remote Equipment Inspection and Assessment    -   4.6.2.1 Timing of the Remote Evaluation Process    -   4.6.2.2 Items Assessed During the Remote Evaluation Process    -   4.6.3 PU and SU Hardware and Software Updates

5. Flow Diagrams

5.1 Communications Handshake

-   -   5.1.1 Overview    -   5.1.2 Communications Handshake, PU Component    -   5.1.3 Communications Handshake, CS Component    -   5.1.4 Handshakes During Diagnostic Checking

5.2 The Data/Commands Handshake

5.3 Audio and Informational Handshakes

-   -   5.3.1 Part I, Audio Handshake    -   5.3.2 Audio Handshake, Part II    -   5.3.2.1 Using Voice Prompts    -   5.3.2.2 Without Voice Prompts, Version 1    -   5.3.2.3 Without Voice Prompts, Version 2    -   5.3.3 Audio Handshake, Part III    -   5.3.4 Informational Handshake

5.4 PU Transport and Setup at the Victim's Side

-   -   5.4.1 PU Transport    -   5.4.2 PU Arrival at Victim; PU Setup    -   5.4.2.1 PU Touchdown and Video Setup    -   5.4.2.2 Audio Communications Adjustment, If Necessary    -   5.4.2.2.1 Audio Communications Overview    -   5.4.2.2.2 Audio Communications Flow Diagram Following PU        Touchdown    -   5.4.2.3 Non-Audio Communication Backups    -   5.4.2.4 Initial Victim Assessment    -   5.4.2.5 Electrode Pad Application    -   5.4.2.6 Electrode Pad Assessment

5.5 Flow Diagrams: Arrhythmia Management

-   -   5.5.1 First Tier Arrhythmia Triage Protocol    -   5.5.1.1 Overview    -   5.5.1.2 Details of Arrhythmia Triage    -   5.5.1.2.1 Bradycardia/Paced Rhythm Decision    -   5.5.1.2.2 Tachycardia/No Tachycardia Decision    -   5.5.1.2.3 Options in the Event that the Rhythm Diagnosis is        Uncertain    -   5.5.1.3 Other Approaches to First Tier Arrhythmia Triage    -   5.5.2 Shock Administration Protocol    -   5.5.3 Second Tier Arrhythmia Triage Protocol    -   5.5.3.1 Overview    -   5.5.3.2 Alternative Tachycardia Termination Techniques    -   5.5.3.3 The MP's Assessment of the Appropriateness of the Use of        Alternative Tachycardia Termination Techniques    -   5.5.3.4 Algorithm for Considering Alternative Tachycardia        Termination Techniques Based on State of Consciousness,        Respiratory Status and Blood Pressure    -   5.5.4 Anti-Tachycardia Pacing    -   5.5.4.1 Background    -   5.5.4.2 Anti-Tachycardia Pacing Protocol    -   5.5.4.3 Other Possible Anti-Tachycardia Pacing Protocols    -   5.5.5 Bradycardia/Pacing Protocol    -   5.5.5.1 Overview    -   5.5.5.2 External Pacing Not in Progress; MP Decision Whether to        Start Pacing    -   5.5.5.3 External Pacing Is in Progress; MP Decision Whether to        Check Underlying Rhythm    -   5.5.5.4 MP Considerations Concerning Termination of Pacing

5.6 Command Confirmation

6. Central Station Screens

6.1 Basic Communications Screens

-   -   6.1.1 Communication Status and Master Control Screen    -   6.1.2 Voice Prompt Screen

6.2 Portable Unit Setup Screens

-   -   6.2.1 Portable Unit Deployment Screen    -   6.2.2 The Video Control and Instruction Screen    -   6.2.3 Initial ECG Screen

6.3 Arrhythmia Management Screens

-   -   6.3.1 Defibrillation Management Screens    -   6.3.1.1 Paths to Main Defibrillation Screen    -   6.3.1.2 Method of Operation: Defibrillation Screens    -   6.3.1.2.1 Default Values: Main Defibrillation Screen    -   6.3.1.2.2 Non-default Values    -   6.3.1.2.2.1 Defibrillation Energy Screen    -   6.3.1.2.2.2 Synchronization Screen    -   6.3.1.2.2.3 Pulse Shape Screen    -   6.3.1.2.2.4 Electrode Setup Screens    -   6.3.1.2.2.4.1 Five Electrode Pad Setup Screen    -   6.3.1.2.2.4.2 Matrix Electrode Pad Setup Screen    -   6.3.1.2.2.4.3 Single Electrode Pad Setup Screen    -   6.3.1.3 Unconventional Defibrillation Methods    -   6.3.1.4 Paths From Main Defibrillation Screen    -   6.3.2 Anti-Tachycardia Pacing Screen    -   6.3.2.1 General Considerations    -   6.3.2.2 Default Values    -   6.3.2.3 Non-Default Values    -   6.3.2.4 Paths from Anti-Tachycardia Pacing Screen    -   6.3.3 Bradycardia Pacing Screens    -   6.3.3.1 Paths to Main Pacing Screen    -   6.3.3.2 Method of Operation: Bradycardia Pacing Screens    -   6.3.3.2.1 Default Values    -   6.3.3.2.1.1 Common versus Different Parameters for Bradycardia        Pacing and for Anti-Tachycardia Pacing    -   6.3.3.2.2 Non-Default Values    -   6.3.3.2.2.1 Pacer Amplitude Screen    -   6.3.3.2.2.2 Bradycardia Pacing Rate Screen    -   6.3.3.2.2.3 Pulse Shape Screen/Pacing    -   6.3.3.2.2.4 Electrode Setup Screens/Pacing    -   6.3.3.2.2.5 Pacemaker Sensing    -   6.3.3.2.2.5.1 Sensing from the Electrode Arrangement with the        Largest R-Wave    -   6.3.3.2.2.5.2 Sensing from the Electrode Arrangement used for        Pacing    -   6.3.3.2.2.5.3 Sensing from an Electrode Arrangement Selected by        the MP    -   6.3.3.2.3 Termination of Pacing    -   6.3.3.3 Paths from Main Pacing Screen

6.4 MP-Directed PU Diagnostic Check and Maintenance Screen

6.5 Master Triage Screen

6.6 Main Screen Menu

6.7 Command Confirmation and Event Log

7. Block Diagrams: Units and Major Components of the System

7.1 The Portable Unit

7.2 The Stationary Unit

7.3 The Master Control Unit

7.4 The Central Station

7.5 The Stationary Unit Decoder

7.6 The Portable Unit Decoder

7.7 The Portable Unit Encoder

7.8 The Central Station Decoder

7.9 The Central Station Encoder

8. Miscellaneous

8.1 Diagnostic Check

8.2 Universal Connectors

8.3 Network of Central Stations

8.4 Multiple Communication Modalities and Routes

8.5 Multiple Possible Routes and Relays Between PU and CS

8.6 Control of an Implantable Cardioverter-Defibrillator by the MP

8.7 Defibrillation Using Two or More Different Shocks in One Victim

8.8 Monitoring Adequacy of Ventilation During Resuscitation UsingPressure and/or Flow Monitoring

8.9 Monitoring Adequacy of Ventilation During Resuscitation UsingTransthoracic Impedance

TABLES 1) Master Control States 1.3.1.2 2) Summary of Figures 1.4 3) ECGRecording Configuration on Five 3.2 Electrode Pad 4) ECG RecordingConfiguration on Five 3.2 Electrode Pad with Seven Sensing Electrodes 5)ECG Recording Configuration on 3.3 Thirty Two Electrode Pad 6) SevenPhases of Activity During A 4.1 Cardiac Arrest 7) Four Layers ofHandshake Linking 4.1.2.1 Enabler and MP 8) PU-CS Routing Analysis andBackup When 4.1.2.4.1 SU is Available 9) Four Layers of HandshakeLinking 4.1.3.2.1 Victim and MP 10) Four Layers of Handshake Linking4.1.6.2 EMT and MP 11) Events During an Hypothetical Cardiac 4.2 Arrest12) Deployment of the Old PU after EMT 4.5.7.1.2 Arrival 13)Communication Choices Using the Second 4.5.7.5.2.2 PU as a Relay 14)Flow Diagrams of Events During a Cardiac Arrest 15) Central StationScreen Summary 16) Signals During Communication (Layer #1) Handshake 17)Testing During Data/Commands (Layer #2) Handshake 18) Testing DuringAudio (Layer #3) Handshake 19) Testing During Enabler-MP Handshake:Which Tests are Abnormal for Each Component Failure 20) Options forCommunications Enhancement During the Four Handshakes of the Enabler-MPLink

Appendices 1) Voice Prompts 2) Abbreviations 1. System Overview

In the text hereinabove and hereinbelow, both of the terms “medicalemergency” and “cardiac arrest” are used to describe the event for whichthe invention may be used. A cardiac arrest is one type of medicalemergency in which collapse occurs because the heart's electrical ormechanical function is severely abnormal. The initial heart rhythmduring a cardiac arrest is usually either ventricular fibrillation (VF),ventricular tachycardia (VT), bradycardia or asystole; Occasionally, therhythm is normal (pulseless electrical activity). A cardiac arrest canbe diagnosed when the electrocardiogram of the victim of a medicalemergency shows VF, VT, asystole or profound bradycardia. Certain typesof bradycardia, VT and other tachycardias may constitute medicalemergencies, although they may not be associated with complete collapse,and thus may not be considered to be cardiac arrests. Certain types ofcollapse, such as pulseless electrical activity, may constitute amedical emergency even though they may be associated with a normal heartrhythm; The absence of a palpable pulse and/or measurable blood pressureis required for this diagnosis.

1.1 Description of the Emergency Scene

FIG. 1 shows an overview of the scene of a medical emergency scene 10during the moments after the victim is first observed. In this preferredembodiment of the invention, an enabler 100, i.e. a person who observesa victim of a medical emergency 102 and wishes to participate in theresuscitation of said victim, begins the process by pressing emergencybutton 106 (hereinafter referred to as “button press”) on portable unit104. Victim 102 may be conscious or unconscious. Enabler 100 is a personwith no prior medical or emergency training.

By pressing the button, the enabler 100 causes the portable unit toestablish a communications link with a central station 300 in whichhighly skilled personnel are situated. A medical professional 301 thenguides enabler 100 through a series of steps, each of which requires nomedical expertise on the part of enabler, that will allow the medicalprofessional to diagnose and, if necessary, directly controlresuscitative maneuvers on victim 102 via portable unit 104. Suchmaneuvers include defibrillating or pacing the heart. Communicationbetween the scene of the medical emergency and the central station maybe via a telephone system 114 (either copper-based, optical fiber based,radio frequency based, or hybrid), or via radio frequency link 116(either direct, with repeaters, with satellite linkages or a hybridsystem). The presence of backup and/or redundant communicationmodalities, results in a highly robust link between the scene of theemergency and the central station. However, in the event that allcommunication systems fail, a backup automatic defibrillation systemallows continued operation of the system.

Referring to FIG. 2A, in the preferred embodiment, portable unit 104 isattached to stationary unit 108, which is anchored to a wall. Emergencybutton 106 is labeled in a manner which allows enabler 100 to easily andrapidly discern that it is to be pressed in the event of a medicalemergency. It may, for instance, have a large red cross on its surface.It may have the words “Medical Emergency” or “Press Button for MedicalEmergency” or other similar wording on its surface or immediatelyadjacent. The words would be plainly visible from a distance.

Portable unit 104 and stationary unit 108 may be situated in any publicplace such as an airport, a shopping mall, a gambling casino, arestaurant, etc. Alternatively these units may be situated in non-publicplaces such as a person's home or an office. Another alternative wouldinvolve the placement of such units within a medical facility, e.g. ahospital, nursing home or rehabilitation facility.

Pressing emergency button 106 causes communication between the portableunit and the central station to be quickly established. Immediatelyfollowing an initial electronic handshaking process, the central stationis automatically informed of the exact location of the portable unit.The medical professional then identifies himself to the enabler 100, andconfirms that both the medical professional and enabler 100 can hear andunderstand each other. The medical professional then inquires as to thenature of the situation that enabler 100 has observed. If the medicalprofessional decides that the resuscitative equipment contained inportable unit 104 will be useful for the resuscitation of victim 102,the medical professional will cause a lock to release the portable unit104, from the stationary unit, 108. The medical professional will tellenabler 100 to detach portable unit 104 from stationary unit 108 bygrasping handles 110, and to quickly carry the portable unit 104 to thevictim's side.

FIG. 2B is another overview of the system, showing the scene of themedical emergency after the medical professional has released theportable unit and instructed the enabler to transport it to the victim'sside. The portable unit 104 is situated immediately adjacent to thevictim 102. Electrode pad 200 has been attached to the chest of victim102. The electrode pad 200 allows a medical professional to observe thevictim's electrocardiogram, and to control the application of electricalenergy to the victim, for either pacing, cardioverting or defibrillatingthe heart. The electrode pad 200 is initially situated within a storagecompartment of portable unit 104. Detailed instructions describingremoval of the electrode pad 200 from the portable unit 104 anddescribing the process of application of the electrode pad 200 to thechest of victim 102 will be provided to enabler 100 by the medicalprofessional. Electrical energy is conveyed between electrode pad 200and the portable unit 104 by a cable 202 which consists of multipleinsulated wires.

The medical professional's ability to instruct the enabler 100 in theproper application of the electrode pad 200 to the victim 102 isenhanced by medical professional's being able to see the victim 102 andto observe the enabler's application of the electrode pad 200. Themedical professional observes the scene via a television camera whichmay be built into the portable unit 104. Video apparatus is containedwithin a video boom 112, which may be extended from the portable unit104, and pointed in any direction. The video apparatus may include oneor more lenses and means for remote focusing. It may further includemeans for collecting light and amplifying it. The projection 112 may bemoved in three dimensions by either enabler 100 or the medicalprofessional, via telemetry signals between the central station and theportable unit 104.

Enabler 100 may be instructed in additional maneuvers by the medicalprofessional. These include various forms of circulatory and/orrespiratory assist for victim 102 including cardiopulmonaryresuscitation.

Portable unit 104 communicates with central station either directly, orindirectly via stationary unit 108. FIG. 2 b shows a radio frequencylink between portable unit 104 and stationary unit 108, but other typesof link are possible including infrared light based or hard-wiring.

1.2 Description of the Central Station

FIG. 3 shows a view of the medical professional's console or controlpanel. The medical professional 301 sits with easy access to multiplevideo displays, inputting devices and communication systems. These allowthe medical professional to evaluate the victim, treat the victim, andcommunicate with the enabler, who is instructed by the medicalprofessional. The video displays allow the medical professional toobserve the physiologic status of the victim of a medical emergency, tohave access to other data relating to the current medical event andprior medical events for this victim, to have access to signal qualityand communication options, access to triage status and triage optionsand access to higher echelons of advice, either from a computer-basedexpert system, or from a super-expert medical professional. Theinputting devices allow the medical professional 301 to directly controlvarious aspects of the management of the medical emergency such asdefibrillation and pacing of the heart. They also allow him to controlthe communications link with the portable unit and enabler. They alsoallow the medical professional 301 to provide audio and videoinstructional information for the enabler.

The victim's electrocardiogram is displayed on screens 302. Manydifferent display formats are possible including one, two or multiplesimultaneous electrocardiogram leads, as well as the ability to freezeand hold a tracing on one screen (for reference or for furtheranalysis), while continuing to view “live” electrocardiograms on anotherscreen. The victim's blood pressure data is displayed on screen 304, andoxygen saturation data is displayed on screen 306. Other parameters ofrespiratory status, blood sugar, body temperature and other physiologicparameters may also be displayed.

The medical professional 301 may observe the victim and the performanceof the enabler at the emergency site on screen 308. The medicalprofessional 301 controls the field to which he has video access bymanipulating the video boom 112 of the portable unit 104. The length andorientation of the video boom may be controlled by the medicalprofessional using joystick 310. The medical professional 301 may alsocontrol the video boom via the keyboard 312, the mouse, 314, or via atouch sensitive screen.

In a preferred embodiment of the system, the medical professional'scarries on an audio dialog with the enabler, and possibly other medicalprofessionals including emergency services local to the victim andincluding higher level medical experts. The medical professional's voiceis picked up by microphone 316, mounted near said medical professional.Alternatively the medical professional may wear a lapel-type microphone,may wear a headset containing a microphone, or may use telephone handset318. The medical professional hears the voice of the person with whom heis communicating via either speakers 320, earphones, a headsetcontaining earphones plus microphone, or telephone handset 318.

If audio communication is not effective for any reason, the medicalprofessional has the option of transmitting and receiving text messagesto and from the enabler. Keyboard 312 may be used to input textmessages. The message, as displayed to the enabler can be seen by themedical professional on screen 322. Text messages from the enabler areviewed by the medical professional on screen 324, and may be printed byprinter 326. Printer 326 may also be used to print other data includingelectrocardiograms, other physiologic data, archived information aboutthe victim's medical history, communications information and/or acomplete log of the current medical event. In the event of completefailure of communications, the portable unit's automatic externaldefibrillation circuits (see below) would allow resuscitative efforts toproceed.

In a preferred embodiment, the medical professional inputs commandswhich control electrical therapy to the victim including defibrillationand pacing. Each of the parameters which control these processes (e.g.pulse energy, pulse width, synchronization) may be selected by themedical professional. One means of selection is via touch sensitivescreens 328, 330, 332, and 334. A menu of possible choices is displayedon the touch sensitive screen. The medical professional selects hischoice by touching the appropriate spot on the screen with either hisfinger or a wand. Alternatively, such choices can be made by moving themouse which moves a pointer on the screen(s), and by clicking over theappropriate choice. The medical professional may also input commands viakeyboard 312, using either the arrow keys to navigate among choicesdisplayed on the screen, or by directly inputting commands that arealphabetic (e.g. “control S” for shock) or numeric (e.g. “100” for shockenergy), or by using the “f keys.” The medical professional my alsoinput commands by voice, using a voice recognition system.

Since the number of possible menus and displays may exceed the number ofvideo screens, the medical professional may select the content of eachscreen by accessing a screen menu. The screen menu lists all possible(touch-sensitive) sub menus and (non-touch-sensitive) displays. Themedical professional uses the screen menu to assign a sub-menu or adisplay to each screen. FIG. 3 shows one such assignment.

Passive screens 336 and 338 are not touch sensitive and are used todisplay information. Examples of such screens would include the eventlog, communications information and the victim's medical history.

Screens 322 and 324 are identical in display content to thecorresponding two screens on the portable unit 104, This allows themedical professional to view exactly what the enabler 100 is viewing.Besides text messages, these screens may be used, at the direction ofthe medical professional, to display instructional videos for theenabler, or, a live video of the medical professional, for purposes ofreassurance or instruction.

In the event that the enabler is himself a medical professional,electrocardiograms or other physiologic data, and defibrillator andpacing control screens may be enabled, and displayed on screens 322 and324.

The medical professional 301 may receive advisory prompts, shown in FIG.3 on the lower portion of screens 330 and 332. Such prompts may includeexpert system based suggestions for medical management, changes in aphysiologic parameter noteworthy enough to bring to the immediateattention of the medical professional, changes in communications status,changes in triage status, or changes in the operating integrity of anypart of the system.

The current time is displayed on screen 340; the elapsed time, from thestart of the emergency call is displayed on screen 342. Other timeintervals, including time since definitive therapy begins, or elapsedtime starting with the estimated moment of the victim's collapse, mayalso be displayed.

Many other display arrangements are possible, including those withdifferent numbers of screens, different geometric arrangements ofscreens and different inputting devices.

An on site data storage system 344 allows the medical professional tohave access to patient databases, pacemaker and implantabledefibrillator information, drug information, expert system programs formanagement of medical emergencies and information about local emergencyresponse teams around the world. It also allows for storage of datapertaining to the current medical emergency.

1.3 Block Diagram of the System 1.3.1 Two Unit System: PU and CentralStation 1.3.1.1 System Operation When PU-CS Communication Is Intact

FIG. 4A is a diagrammatic overview of the system, showing greater detailthan FIG. 1. It shows the flow of information (including the medicalprofessional's control of defibrillation and pacing) within the system,after it has been attached to the victim 102. To simplify thepresentation, FIG. 4A shows an embodiment of the system in which theportable unit 104 communicates directly with the central station 300,without a stationary unit 108 interposed between. FIG. 4B is analogousto FIG. 4A, but it includes the stationary unit.

Referring to FIG. 4A, portable unit 104 obtains the ECG and otherphysiologic data from the victim 102. These signals are amplified,filtered, digitized and processed by ECG and physiologic data processingunit 118.

Processing unit 118 has three outputs: a) to the PU encoder 120; b) via<AA> to “AED/P,” the automatic external defibrillator/pacer analysis,logic and control unit 128; and c) via <AA> to defibrillator and pacingcontrol circuits 131. The signals from data processing unit 118 to thePU encoder 120 (described in detail below) are encoded and transmittedto the central station 300 by portable unit transmitter 122. Theportable unit transmitter may output into either a public telephonenetwork, the Internet via public telephone network, or a privatecommunication system, either hard-wired, radio frequency, or hybrid. Thesignals from data processing unit 118, via <AA>, are used by the AED/Panalysis, logic and control unit 128 which automatically controlsdefibrillation and pacing, in the event of communications failurebetween the PU and the CS. The signals from data processing unit 118,via <AA> to the defibrillator pacing and control circuits 131: a) may beused to provide a synchronization (timing) signal for defibrillation andb) is used to provide inhibitory signals if pacing is performed forbradycardia.

Referring again to inputs to the PU, audio input signals including thevoice of enabler 100 and video input signals showing the victim and thescene of the emergency are amplified, filtered, digitized and processedby the portable unit audio and video input processing units 124. Theaudio and video data is then encoded by portable unit encoder 120, andthen transmitted by portable unit transmitter 122.

Central station 300 receives information sent by the portable unit viacentral station receiver 346. The receiver can receive either radiofrequency or hard-wired signals. The signals are decoded by centralstation decoder 348 (described in detail as FIG. 53). The decodersupplies ECG and physiologic data signals which are processed by the ECGand physiologic data processing unit 350 and displayed on theappropriate screens (302, 304 and 306, in FIG. 3) for viewing by themedical professional 301. The decoder output also supplies audio andvideo information which is processed by the central station audio andvideo output processing units 352, and thus heard and seen by themedical professional 301.

Using the ECG data, the medical professional can diagnose an abnormalheart rhythm in a victim. In the event that the victim has suffered acardiac arrest, the medical professional can cause the portable unit tosupply a defibrillating shock to the victim. Lesser degrees ofabnormality can also be diagnosed and treated by the medicalprofessional. The medical professional would defibrillate a patient byselecting each of a number of parameters including shock energy, pulseconfiguration, the particular electrodes of the defibrillator padthrough which energy is to pass (see ahead), and timing of shock. Thevalue or choice for each of these parameters would be inputted by themedical professional through any of a variety of input devices (shown inFIG. 3) including touch sensitive screens 328, 330, 332 and 334;keyboard 312, or mouse 314. The command signals are processed by commandsignal processing unit 354. These signals are then encoded by thecentral station encoder (described separately in FIG. 54) and thentransmitted by the central station transmitter 358. The central stationtransmitter may interface with a variety of communication systems, as isthe case with the portable unit transmitter 122, described previously.

The medical professional accomplishes a number of desirable goals byspeaking with the enabler. These include:

a) carrying on an initial dialogue with the enabler to assess whetherthese is an emergency and whether use of the portable unit 104 isappropriate;

b) supplying instructions for properly transporting the unit and settingit up at the side of the victim;

c) supplying instruction for properly placing a defibrillation pad onthe chest of the victim;

d) informing the enabler and other bystanders to avoid contact with thevictim at the moment of a defibrillation shock;

e) instructing the enabler in cardiopulmonary resuscitation;

f) instructing the enabler to obtain, if possible, identifyinginformation about the victim (to facilitate patient database access);

g) prompting the enabler to supply neurologic information, specifically,the enabler's assessment of the state of consciousness or responsivenessof the victim; and

h) reassuring the enabler and other bystanders, since a cardiac arrestsituation is often attended by a certain degree of pandemonium andchaos.

The medical professional's audio and video inputs are processed by thecentral station audio and video processing unit 360. Afteramplification, filtering, digitization, formatting and other signalprocessing, these signals are passed to the central station encoder 356,and then transmitted by the central station transmitter 358 along withcommand signals. Central station video inputs include instructionalmaterials related to pad placement and the correct performance ofcardiopulmonary resuscitation. Allowing the enabler to see the medicalprofessional, though not medically necessary may, in some cases, providea measure of reassurance for an anxious enabler, and/or during adifficult resuscitation effort.

Audio and video information transmitted by the central station isreceived by the portable unit receiver 126, decoded by decoder 127, andamplified and processed by the portable unit audio and video outputprocessing unit 134. This unit drives speakers and/or headphones, and avideo display for enabler.

The medical professional's commands for: a) the master control unit 130;and b) the portable unit defibrillator and pacing control circuits 131,are received by portable unit receiver 126 and decoded by portable unitdecoder 127. As long as communication between the central station andthe portable unit is intact, commands from the central station,outputting from decoder 127 are passed through master control unit 130to defibrillator and pacing control circuits 131. Control circuits 131control defibrillator and pacing output circuits 132, the medium voltage(used for pacing) and high voltage (used for defibrillation) generatingapparatus within the portable unit. Specifically, defibrillator andpacing control circuits 131 control all aspects of defibrillation pulseproduction including onset of capacitor charging, timing of discharge,pulse amplitude, shape and energy. If pacing (a medium voltagerepetitive electrical stimulation) is necessary, circuits 131 controlthe pacing rate and mode, as well as pulse amplitude, shape and energy.The defibrillator and pacing output of the unit is coupled to the victimvia cable 202 and electrode pad 200.

1.3.1.2 AED Backup in the Event of Communication Failure; Role of MasterControl Unit

In the event of a failure of communication between the portable unit 104and the central station 300, the portable unit may utilize automaticexternal defibrillator/pacer analysis, logic and control circuits 128,instead of commands from the medical professional, for control of PUelectrical therapy. Automatic external defibrillators, AED's, as theyare known in the art, contain circuits which analyze electrocardiogramsignals, and, if ventricular fibrillation is detected, apply a highvoltage shock to the victim of a cardiac arrest. They can providepre-programmed voice prompts, for user instruction.

There are two situations which would result in transfer of control ofdefibrillation from the medical professional to the AED/P within the PU.The first such situation is in the event of failure of communications ineither direction (or both directions) between the portable unit and thecentral station. In a preferred embodiment of the invention, a complexsystem of handshakes between the PU and the CS, described below, is usedto constantly monitor the integrity of communications. The second suchsituation is in the event that the MP decides that the quality of thecommunication link is inadequate. At such time, he may send a controlsignal which transfers control of the PU to the AED/P.

Control of pacing and defibrillation is via the master control unit 130.The master control unit is, at all times, in one of five possiblestates. The particular state that it is in, determines who or what willcontrol the major functions of the portable unit. Under normal operatingconditions, the PU is controlled by the medical professional. But undercertain circumstances, it becomes desirable to allow control by eitherthe AED/P in the PU, or by an on-scene emergency medical team, or “EMT.”(Hereinafter EMT will be used to refer to both the entire emergencymedical team and an individual member of the team who may communicatewith the MP and who may be given access to PU control. EMT may alsorefer to a physician or other highly qualified person at the scene ofthe cardiac arrest.) Functions controlled by the master control unit 130include high voltage charging and delivery and release of the PU lockingmechanism. The matrix which shows the relationships between: a) mastercontrol unit state; b) who or what is in control; and c) which functionsare subject to this control is shown in table 1, and described below.

TABLE 1 Master Control States Charge Deliver Control Master PU High HighOf PU Lock Control Control Voltage Voltage AED/P by TSS Release State ByEnable Enable Enable Enable Enable 0 MP No No No No No 1 MP Yes Yes NoNo Yes 2 AED/P Yes Yes Yes No Yes 3 EMT Yes Yes No Yes Yes 4 MP Yes NoNo No NoThe state of the master control unit determines whether defibrillationand pacing are controlled by the MP, by the AED/P circuits, or by anon-scene emergency medical team. State 0 is the quiescent state, inwhich the PU remains, until activated when an enabler presses theemergency button 106. If, after enabler describes the emergency to theMP, the MP decides to release the PU, MP sends a command to the PU whichcauses master control unit 130 to enter state 1. In state 1, highvoltage charging and delivery is enabled, and lock release is enabled.In the event that proper communication between the MP and the enablercan not be established or maintained, the master control unit entersstate 2. In state 2, lock release no longer requires MP approval, andthe PU functions as an AED/P. If a qualified Emergency Medical Teamarrives, the MP may transfer control of the PU to the EMT by sending acommand to the PU which causes the master control unit to enter state 3.In state 3, the EMT controls the PU by selecting commands on the PUtouch sensitive screen, “TSS,” in much the same way that the MP would.Master control state 4 (see Sections 4.5.7.4.4 and 4.6.2), is enteredwhen a diagnostic check of the PU is performed. In state 4, although thehigh voltage circuits may be charged, high voltage may not be delivered.

The AED/P analysis, logic and control unit 128 receives ECG informationfrom ECG and physiologic data input processing unit 118 (describedabove) via <AA>. If VF is detected and if the master control unit hasenabled control of defibrillation and pacing by the AED/P, the AED/Pcontrol unit 128 would have access to defibrillator and pacing controlcircuits 131. In this situation, a defibrillation control signal fromthe AED/P unit 128 would be relayed through master control unit 130 andcause defibrillator and pacing control circuits 131 to causedefibrillator and pacing output circuits 132 to provide a shock to thevictim. The AED/P unit 128 also provides pre-programmed audioinstructional information, which is amplified and processed by audio andvideo output unit 134.

1.3.2 Three Unit System: Portable Unit, Stationary Unit and CentralStation

In the aforementioned embodiment, the portable unit and the centralstation communicate directly. In a preferred embodiment of theinvention, the portable unit and the central station communicate via astationary unit, 108, as shown in FIG. 4B. This three-unit arrangementallows for a portable unit with a less sophisticated receiver, and aless powerful transmitter. It will enhance the ability of the portableunit to remain in communication with the central station, even whenoperating deep inside of a building or other structure whereelectromagnetic wave propagation from the outside may be significantlyattenuated.

As shown in FIG. 4B, the stationary unit functions as a repeater,consisting of two receivers and two transmitters. Stationary unitshort-range receiver 136 receives signals from the portable unittransmitter 122. The information contained in these signals istransmitted by stationary unit long-range transmitter 138 to centralstation receiver 346. As was the case with the two unit system describedin FIG. 4A (in which the portable unit communicated with the centralstation without an intermediary stationary unit), in the three-unitsystem described in FIG. 4B, the stationary unit long range transmitter138 may output into either a public telephone network, the Internet viapublic telephone network, or a private communication system, eitherhard-wired, radio frequency, or hybrid.

Signals sent by the central station transmitter 358 are received by thestationary unit long-range receiver 140. Communication modalities for CStransmitter 358 and SU long-range receiver are similar to thosepreviously mentioned for the SU long-range transmitter 138 and CSreceiver 346. The information contained in these signal is transmittedby the SU short range transmitter 142 to the PU receiver 126 using acommunication modality similar to the link between the PU transmitter122 and the SU short range receiver 136.

The medical professional can control routing of signals between thestationary unit and the central station. In particular, he can controlwhich of a multiplicity of communication options are used for theselinks. This process includes the transmission of routing control signalsfrom the CS transmitter 358 to the SU long range receiver, from whencethey are decoded by SU decoder 144 (described below).

Other communication options under the control of the MP include:

a) the option to switch from a three unit system (i.e. a system whichincludes the SU) to a two unit system (PU and CS, without SU) while thesystem is in use;

b) the option to switch from a two unit to a three unit system while thesystem is in use;

c) the control of the communications link (e.g. public telephonenetwork, private network, radio frequency, Internet, etc.) between theSU and the PU (This process includes the transmission of routing controlsignals from the CS transmitter 358 to the PU long range receiver, fromwhence they are decoded by PU decoder 127 [described below].); and

d) the option to allow communication control (viz. the aforementionedchoices involving routing and selection of communications modality) tobe: (i) automatic (i.e. performed by the system), (ii) manual (i.e.performed by the MP), or (iii) a hybrid involving automatic control withthe option of manual override.

1.4 Figure Assignments

The figure assignments for the overviews of the system, as well as allother figures is shown below, in Table 2.

TABLE 2 Summary of Figures FIG. Subject Overviews  1 System Overview 2A,2B Emergency Scene Overviews  3 View of Central Station 4A, 4B BlockDiagrams of Flow of Information among PU, SU, CS; Enabler, Victim andMedical Professional Electrode Pads 5A-G Views of Defibrillating/PacingPads Portable and Stationary Unit Hardware  6-11 Views of Portable Unitand of Stationary Unit Flow Diagrams: Four Handshakes ComprisingEnabler-MP Link 12 Communication Handshake - PU component 13Communication Handshake - CS component 14 Data/Commands Handshake 15Audio Handshake 16 Informational Handshake and PU Lock Release FlowDiagrams: Portable Unit Deployment 17 Transport of PU to victim 18 PUSetup at victim's side Flow Diagrams: Arrhythmia Management 19Arrhythmia Diagnosis 20 VF Treatment 21 Second Tier Arrhythmia Treatment22 Anti-Tachycardia Pacing 23 Bradycardia Treatment Flow Diagram:Confirmation Signals 24 MP Command Execution and Confirmation, and PUTelemetry CS Screens 25-44 Control Screens for Medical ProfessionalBlock Diagrams: Units and Major Components of the System 45-49 PortableUnit, Stationary Unit and Central Station: Block Diagrams 50-54 Decodersand Encoders: Block Diagrams Miscellaneous 55A-B Diagnostic Check: BlockDiagram 56A-F Universal Connectors (Pads to Portable Unit) 57 Network ofCentral Stations: Block Diagram 58 Communication Options 59 SignalRouting: Block Diagram 60 Control of ICD via CS 61 Resuscitation withTwo Defibrillators 62 Resuscitation with Pressure and Flow Monitoring 63Transthoracic Impedance Monitoring

2. Portable Unit and Stationary Unit: Exterior Elements 2.1 PortableUnit: Front and Right Side Panels

FIG. 6A shows the portable unit 104 attached to the stationary unit 108,as would be the case prior to removal of the portable unit by anenabler. Emergency button 106 is conspicuous, plainly visible from adistance. Handles 110 facilitate enabler's detachment of the PU from theSU, and enabler's carrying the PU to the victim's side.

Speakers 146 allow the enabler to hear the MP's voice. They may besituated in any one of a number of different geometrical arrangements,and their number may vary from a single speaker, to one or more on oneor more faces of the PU. In general, their location would optimizeenabler hearing, regardless of how the PU is put down and oriented atthe victim's side. One or more microphones 148 are similarly placed toallow the MP to hear enabler, regardless of PU orientation. Telephonehandset 150 may be optionally used by enabler in a noisy environment orif he is hard of hearing. The decision to use it may be made by theenabler himself, or at the suggestion of the medical professional in thecentral station. The handset is in electrical communication with the PUcommunication system via multi-wire cable 152. {Alternatively, thehandset may have a wireless link to the PU.}

A female telephone jack 153 on the PU allows it to receive informationfrom another PU (see Section 4.5.7.5.2.2). A female telephone jack 155on the SU allows it to receive information from another PU (see FIG. 9and Sections 4.5.7.5.1 and 4.5.7.5.2.2).

Video camera 154 allows the medical professional to view the environmentof the portable unit. Before the unit is activated by the enabler, theouter optical surface of the camera is flush with the surface of the PU.However, the viewing apparatus is deployed on an extensible boom (112 inFIG. 2B; also well seen in FIG. 6B). The boom can be extended from theunit, and aimed in any direction, under the control of the medicalprofessional. Video input from the portable unit allows the MP a numberof advantages including:

a) the ability to observe anyone who presses emergency button 106; thiswill (i) act as a deterrent to inappropriate or prank activation of theunit, and (ii) allow the MP to more easily determine when such a prankactivation is occurring;

b) the ability to instruct the enabler in the placement of electrodepad(s), by either (i) verbally instructing the enabler as he applies theelectrode pad(s), or (ii) visually instructing the enabler by showinghim a live video of the victim's torso, upon which MP has superimposedvisual prompts such as arrows, an outline of the pad, or a cartoonversion of the pad;

c) the ability to observe whether enabler has correctly placed electrodepad(s) 202 (FIG. 2B);

d) the ability to instruct the enabler in other resuscitation relatedacts, including cardiopulmonary resuscitation by either (i) verballyinstructing the enabler as her performs these maneuvers, or (ii)visually instructing the enabler by showing him a live video of thevictim, upon which MP has superimposed visual prompts appropriate forthe maneuver;

e) the ability to observe the victim; and

f) the ability to observe the portable unit itself; this would beaccomplished by extending the boom outside of the unit, and causing theboom to angulate at one or more points along its shaft, so that the neteffect is a 180 degree reversal in the angle at which the camera isoriented; this would allow intermittent inspection of the unit by theMP.

Portable unit video screens 156 allow the user of the portable unit toview video information. As mentioned previously such informationincludes: a) text messages from the MP, in the event that the enablercan not hear the MP's voice; b) instructional video regarding (i)correct electrode pad placement and orientation, and (ii) properexecution of various maneuvers including cardiopulmonary resuscitation;and c) the medical professional.

In one embodiment of the invention, one or more of the screens would betouch sensitive. In the event that the MP can not properly hear theenabler, the MP may instruct the enabler to respond by touching virtualbuttons on the screen with labels such as “yes” and “no”. Alternatively,other potential answers to MP questions may be displayed as virtualbuttons. Alternatively, a virtual keyboard may be displayed, to allowenabler to make a more detailed textual response.

Finally, in the event that the enabler is replaced at some point duringthe emergency by an EMT, it will be possible to allow the EMT to: a)view the victim's electrocardiogram; and b) have access to control ofdefibrillation and pacing by making one or both of screens 156 touchsensitive. In this situation, the medical professional in the centralstation, upon receiving evidence that the EMT is properly identified andor qualified, would send a command to the PU (See discussion of mastercontrol, ahead; Also see Table 1.) which would enable control of the PUvia the touch sensitive screens and display the victim'selectrocardiogram on these screens. The two screens on the PU would thenfunction in a manner analogous to the control panel in the centralstation.

There are many possible ways in which the screens may be arrangedgeometrically. There may be one or more screens, or none. Finally“screen-in-screen” and split screen displays are possible.

Door 158 covers a tool-kit, the contents of which are visible in FIGS.7A and 7B. The door is locked until either: a) the MP releases it; or b)the PU is detached from the SU and placed down on the ground or otherfirm surface. Knob 160 facilitates enabler's opening of the door, onceit has been released.

Antenna 162 allows the PU to be in radio communication with the SU. Theantenna may be fixed in length, extendible (and retractable) manually,or extendible (and retractable) in response to a command by the MP. Itmay be contained entirely within the PU housing at all times; or it maylie partially or fully outside of the PU housing at all times; or itmay, prior to the emergency, be situated entirely within the PU and beextended outside of the housing during the emergency, at the discretionof the MP. The antenna may also allow communication directly with thecentral station, i.e. without doing so via the SU. More than one antennamay be used to optimize communications over a wide range of frequencies.

Antenna 164 allows the SU 108 to be in radio communication with the PU104. The antenna may be fixed in length, extendible (and retractable)manually, or extendible (and retractable) in response to a command bythe MP. It may be contained entirely within the SU housing at all times;or it may lie partially or fully outside of the SU housing at all times;or it may, prior to the emergency, be situated entirely within the SUand be extended outside of the housing during the emergency, at thediscretion of the MP. Either the same antenna or another one (with orwithout the same external control options as antenna 164) may be used toallow the SU to communicate via radio frequency with the CS. There maybe additional SU antennas to optimize communications a) between PU andSU, and b) between SU and CS over a wide range of frequencies.

FIG. 6B shows portable unit 104 without stationary unit 108. It showspartial extension of the video boom 112. It also shows door 158 in theopen position, revealing multiple shelves and compartments within thetool-kit.

2.2 Portable Unit: Tool-kit

FIG. 7A shows the contents of the tool-kit. Five compartments 166A-166Econtain electrode pads of various shapes and configurations. Each one isalready wired into the portable unit, and ready to be applied to thevictim. The choice of which of the pads is to be used, is made by themedical professional. Element 168 is a headset with microphone, whichmay make it easier for either the enabler or the medical professional tohear, in a noisy environment. The headset-microphone unit may bewireless, or hard-wired into the portable unit. Element 170 is a pair ofscissors, to be used by the enabler, if necessary, to cut the shirt orblouse of a victim, in order to allow rapid placement of the electrodepad against the skin of the victim. Element 172 is a blood pressurecuff. It is of the automatically inflating and recording variety, as isknown in the art. Upon instruction by the medical professional, enablerplaces it around the arm of a victim, allowing the MP in the centralstation to have intermittent blood pressure readings. Element 174 is apulse oximetry transducer and holder. Upon instruction by the MP,enabler places it around the finger of a victim, allowing the MP in thecentral station to determine the victim's arterial oxygen saturation.Element 176 is a telephone wire and jack. One end of the wire isconnected directly to the PU, allowing it to have a hard-wired interfacewith the public telephone network. The free end of the wire, terminatingin a male jack, may be used by the enabler or EMT to connect the unit tothe public telephone network, in the event that wireless communicationto or from the portable unit is inadequate. Compartment 177 contains oneor more spare pads which terminate in Universal Connectors (see ahead)but which are not, while stored in compartment 177, wired into thesystem. Compartment 177 also contains any one or more of a variety ofitems, including spare items for any of the aforementioned tool-kitsupplies, an oral airway, gloves, telephone cable extensions, anapparatus for measuring the victim's cardiac output, the data from whichmay be transmitted to the MP (along with other victim data), andapparatus to assist in providing respiratory support for the victim. Itmay also contain a variety of items to be used by a physician, nurse,emergency medical technician including medications, intravenousadministration fluids and apparatus and a stethoscope.

FIG. 7B shows a side view of the upper five compartments 166A-166E ofthe tool-kit. Item 204 is a defibrillating pad which contains five largeelectrodes, and which may additionally contain seven small electrodesfor recording the electrocardiogram. Cable 212A electrically connectsthe pad to the female version of the universal connector 218A (for thepad without ECG electrodes) or 218B (for the pad with ECG electrodes).This mates with the male version of the universal connector 220A, whichis electrically connected to the portable unit via cable 222.

Electrode pad 206 is similar to pad 204, in terms of electrode contentand configuration, but its shape has been modified to allow greaterconformity to the female torso. It is connected by cable 212B to femaleuniversal connector 218B, which mates with male universal connector220B, which is connected to the portable unit by cable 224.

Electrode pad 208 contains a matrix of 32 electrodes. It is connected bycable 214 to female universal connector 218C, which mates with maleuniversal connector 220C, which is connected to the portable unit bycable 226.

Electrode pads 210 each consist of a single defibrillating/pacingelectrode. They are connected by wires 216 to female universal connector218D, which mates with male universal connector 220D, which is connectedto the portable unit by cable 228. Pads 210 are easily distinguishedfrom each other, by either color, numeric markings, alphabetic markings,or any combination of these. They would be selected at the discretion ofthe medical professional, and two or more would be positioned under thedirection of the MP.

Mini-pads 211 are intended for placement on the extremities forrecording the ECG, and are not used as defibrillating/pacing electrodes.They are to be used when the MP decides that there is no need fordefibrillation or pacing. They could be used when a conscious victimeither doesn't need or refuses to allow the placement ofdefibrillating/pacing electrodes on the torso. They are connected bycable 217 to female universal connector 218E, which mates with maleuniversal connector 220E, which is connected to the portable unit bycable 229. Labels RA, LA, RL and LL on the mini-pads refer to right arm,left arm, right leg and left leg, the intended placement locations. Themini-pads could also be color or number coded.

Individual defibrillating electrodes 210 and ECG electrodes 211 are wellknown in the art, and hence no further description of these elements isnecessary. Different shapes and numbers of these single pads arepossible.

Cables 212A, 212B, 214, 216 and 217 are of sufficient length to extendfrom the portable unit to the victim. Universal connectors 218A-218E and220A-220E would ordinarily remain inside of the portable unit tool-kitcompartment during use. However, cables 222, 224, 226, 228 and 229 areof sufficient length so that pulling on cables 212A, 212B, 214, 216 and217 exposes the universal connector pair, allowing an already usedelectrode pad to be easily replaced.

2.3 Portable Unit: Rear and Left Side Panel

FIG. 8 shows a view of the portable unit from the back, also showing theleft side of the unit, i.e. the side opposite that which containstelephone handset 150. The back contains two or more sensor switches178. These are push-button type switches, with a spring to keep thecenter dowel normally extended outwards. In the preferred embodiment,when the PU is not in use, the back of the PU is in close proximity tothe outer surface of the stationary unit 108 (see FIGS. 6A and 9). Thisproximity results in the dowel of sensor switches 178 being pushed in.When the PU is removed from the SU, the spring-loaded dowel pops out,the sensor switch changes state, allowing the MP to know that the PU wasremoved from the SU. When the PU is placed on a surface such that itsback faces down, the MP is once again notified, since sensor switches178 will again change state as the dowel is pushed back in. And when thePU is later reconnected to the SU, the MP can gauge the adequacy of thereconnection procedure by the response of sensor switches 178.

The sensor switches may have more than two positions, allowing the MP toascertain with greater accuracy whether the PU has been properlypositioned during replacement. When three or more sensors are present,they may be distributed both horizontally and vertically, allowing theMP to have three dimensional information about the position of the PU asit is replaced, and thereby allowing the MP to more fully guide theperson performing the PU replacement (see Section 4.5.7.4.3).

Four feet 180 allow the PU, once separated from the SU, to rest on aflat surface, with back side facing down, but without the back beingflush against the flat surface.

In a preferred embodiment of the invention the PU, in its quiescentstate, is locked to the SU. The SU is shown in FIG. 9. Receptacle andelectromagnetic lock 182, FIG. 8, admits projection 194, FIG. 9 from theSU, to which it locks. This prevents removal of the PU from the SU byunauthorized persons. After the medical professional determines that aparticular situation warrants the use of the PU, he sends a signal fromthe central station which causes the electromagnetic lock 182 to releaseits hold on projection 194.

In the event that either the lock release signal is not properlyreceived or processed, or in the event of mechanical failure in theelectromagnetic release mechanism, a backup, purely mechanical releasemechanism is present. Combination lock and release mechanism 184consists of a combination type lock, 184A as is known in the art. Whenenabler correctly turns its one or more wheels to the correctcombination, he can push lever 184B which causes the release ofprojection 194. The combination would be made available to enabler byvoice or text message, when appropriate. The combination lock andrelease mechanism are seen on the side of the PU opposite the side whichcontains telephone handset 150.

Embodiments of the invention without an SU are possible. Embodiments ofthe invention in which the locking projection 194 comes form astationary object other than a stationary unit are possible; forexample, the locking projection may be attached directly to a wall.Embodiments of the invention without a lock are also possible.

Embodiments of the invention with other backup lock release mechanismsare possible including: a) an electrical mechanism which activelyreleases the lock in the event of communications failure (lockingmechanism normally closed); b) an electrical mechanism which passivelyreleases the lock in the event of communications failure (lockingmechanism normally open); and c) lock releases which include bothmechanical mechanisms (the aforementioned) and electrical mechanisms(either (a) or (b)).

Element 186 is a power connector, which feeds electrical power into theportable unit. This source of power is used to operate the PU 104 and tocharge its batteries, while it is in contact with the stationary unit108. The PU power connector connects to the SU power connector 192, FIG.9. Embodiments of the invention in which the PU receives electricalpower directly from an alternating current source are possible.Embodiments of the invention in which the PU has long shelf-lifebatteries and does not have an alternating current supply are alsopossible.

Element 188, FIG. 8 is the PU telemetry connector which mates with theSU telemetry connector 190, FIG. 9. These telemetry connectors carryinformation between PU 104 and SU 108 before they have been separated.Such information includes audio and video signals, text messages andtelemetry signals between the MP and the enabler. In a preferredembodiment of the invention, the SU serves as an intermediatecommunications link between the PU and the central station. Embodimentsin which the PU may or must communicate directly with the centralstation are also possible. Such an embodiment may have an external maletelephone jack (such as element 176 within the tool-kit) for attachmentto the public telephone network.

The left side also contains a magnetic card reading device 185. Thisallows the MP to have access to the information on a card which maycontain victim medical history. It also allows the MP to have access toinformation on a card which properly identifies EMT personnel, beforecontrol of the PU is transferred.

2.4 Stationary Unit: Front and Side Panels

The stationary unit 108 is L-shaped, allowing its lower portion tosupport the PU. Line cord and plug 196 allow for supply of outsidepower. Telephone cable and male jack 198 allow for connection of the SUto the public telephone network. Female telephone jack 155 allows the SUto receive a direct telephone connection from a PU. The SU may have fourdepressions in its surface, positioned where the PU feet 180 come incontact with it. These depressions are wide enough to admit the PU feet,and are of a depth that is less than the height of the PU feet. Thisallows the PU feet to partially penetrate the SU surface. This geometry,along with sensor switches 178 having more than two positions, allowsthe MP to distinguish:

a) when the PU has been detached from the SU by the enabler (all centerdowels of switches 178 in the fully extended position); from

b) when the PU is placed properly on the ground or another level surface(all center dowels of switches 178 in the partially extended position);from

c) when the PU has been properly returned to its correct position on theSU shelf (all center dowels of switches 178 in the fully retractedposition); from

d) when the PU is improperly positioned on the SU shelf (not all centerdowels of switches 178 fully retracted).

2.5 Portable Unit: Screens

FIGS. 10 and 11 show various configurations for PU screens 156. (SeeFIG. 6A for frontal PU view.)

The left screen in FIG. 10 shows an instructional video. In the exampleshown, a cartoon 365 of the victim is seen along with cartoondesignations of ideal electrode pad locations 366. Alternatively, thescreen may show the actual victim 102, visualized by PU video camera154; with superimposed markings or overlays, manipulated by the MP,indicating desired electrode pad placement. Alternatively, otherinstructional videos including techniques of cardiopulmonaryresuscitation may be displayed. Alternatively, a video display of themedical professional in the central station may be displayed.

The right screen in FIG. 10 shows a text message from the medicalprofessional 301 in the central station 300. Such messages may beutilized in the event of poor quality reception of CS signals at the PU,a noisy emergency scene, or a heard-of-hearing enabler.

FIG. 11 shows the use of the PU screens in a touch sensitive mode. Theleft PU screen shows a control panel similar to that utilized by themedical professional in the central station. This screen is displayedonly under special circumstances. The MP can enable local (i.e.victim-side) control of the portable unit, in the event of arrival oftrained medical personnel at the emergency scene, or if the enablerhimself is a qualified medical professional. The MP enables EMT controlof the PU by sending a command to set the master control unit 130 tostate 3 (see Table 1, above). When EMT control is enabled by the MP, thevictim's electrocardiogram tracing 367 is displayed. Virtual controlbuttons 368 on a touch sensitive control screen allow control ofdefibrillation, pacing, monitoring and other functions. The on-siteprofessional would be able to access any of the portable unit controlscreens available to the central station medical professional.

The right screen in FIG. 11 shows a virtual keyboard 369, with a “YES”key 370, a “NO” key 371 and “hot-keys” 372. This screen allows theenabler 100 to send text messages to the medical professional in theevent of poor quality audio reception of PU signals at the CS, or in theevent of a noisy emergency scene.

The screen functions shown in FIGS. 10 and 11 need not occupy a fullscreen. Screen-in-screen and split screen displays are also possible.

3.0 Electrode Pads 3.1 Physiology of Defibrillation

The termination of ventricular fibrillation during a cardiac arrest isaccomplished by passing a brief, high voltage pulse between twoelectrically conducting pads on a victim's chest. Since the success ofthe defibrillating pulse is dependent on the achievement of sufficientvoltage gradient, over sufficient volume of heart tissue, properpositioning of the defibrillating electrodes is critical. If theelectrodes are too close to each other, regions of cardiac muscle notnear the electrodes will have insufficient voltage gradient, and thedefibrillation attempt will be unsuccessful. Similarly, if theelectrodes are not sufficiently near the heart, an unsuccessfuldefibrillation attempt may ensue.

Standard operating procedure for defibrillation calls for the passage ofan electric current between two pads on the victim's chest, one placedhigh on the chest to the right of the midline, and one placed on the farleft side of the chest, beneath the nipple. Alternate approaches involvea single electrode on the chest surface (generally referred to asanterior) and another electrode on the back (generally referred to asposterior.

In the preferred embodiment of the invention, the medical professionalhas access to more than two defibrillation electrodes. This allows theMP to select what he believes to be the optimum vector or pathway fordefibrillation energy applications. If the first defibrillating shock isunsuccessful, the MP, when more than two defibrillation electrodes arepresent, would be able to change the pathway of defibrillation energyfor a subsequent shock, by changing the choice of electrodes. Theability to change the choice of electrodes also allows the MP tocompensate for inaccuracies in positioning and/or orienting theelectrode pad. It also allows the MP to make adjustments for differentvictim sizes and different heart sizes.

3.2 Torso-Shaped Multi-Electrode Pads

FIG. 5A shows the non-victim side of a five electrode “pad” 204A It istorso shaped, with an extended portion, labeled “VICTIM'S LEFT” which isintended to wrap around the victims left side, that is, the victim'sleft axillary region, slightly below the level of the breast. Individualelectrodes, as are known in the art, are located at 230, 232, 234, 236and 238, each of which contains electrically conductive material on thepatient side of the pad. A wire extends from each electrode; the fivewires, though insulated from each other, coalesce to form cable 212A.Easily seen labels reading “NECK” and “VICTIM'S LEFT” are intended tohelp the enabler properly position the pad on the victim's torso.

The selection of defibrillating electrode location generally calls forhaving as much of the heart's mass lying on a direct path between thedefibrillating electrodes. Therefore, the typical defibrillation effortwould entail the application of energy between electrode 230, labeled α,located over the right upper torso; and electrode 236, labeled δ,located beneath the left breast. If such a shock did not result in therestoration of a normal rhythm, a second effort involving electrodes 230(α) and 238 (ε) would be a reasonable choice. The α-ε pair might be agood first choice for a very large patient. This choice, and all otherchoices of electrodes would be made by the medical professional'sselecting these electrodes from among a menu of options. With a fiveelectrode pad, the MP may choose any of ten possible pairs ofelectrodes. (The value of ten ignores polarity considerations.) The MPmay elect to apply energy when two or more electrodes are madeelectrically common. An example of this would be to make electrodes 236(δ) and 238 (ε) electrically common, and to apply energy betweenelectrode 230 (α) and the composite δ/ε electrode. In principle, the useof 3, 4 and 5 electrode combinations increases the number of possibleelectrode combinations 90. (The value of 90 ignores polarityconsiderations.). Although in practice, many of these 90 combinationswould not be clinically sensible, some would be.

In the event that the electrode pad is improperly positioned or orientedon the torso of the victim, the presence of a multiplicity of electrodesgives the MP some latitude in correcting the error, without having toask the enabler to remove and reposition the pad. For example, if thepad were rotated 90 degrees, such that electrode 230 (α) was positionedat the left (instead of right) upper torso, and electrode 234 (γ) waspositioned at the right upper torso; the MP could apply energy betweenelectrodes 234 (γ) and 232 (β), accomplishing what a standard α-δapplication would, had the pad been properly oriented.

In the event that one or more electrodes is making poor contact with thepatient, the MP can identify the poorly contacting electrode(s) and caneither work around it or ask the enabler to correct the condition.Circuitry within the PU performs impedance measurements between certainelectrode combinations to identify poorly contacting electrode(s). Foreach measurement, one electrode is electrically isolated, and the otherfour electrodes are electrically common. For example, the MP would knowthat the δ electrode is making poor contact if the impedance measurementof δ vs. electrically common α/β/γ/ε is high, while the impedance valueof each other combination of one electrode against the other four, e.g.α vs. β/γ/δ/ε is low. Using such an approach, a low impedancemeasurement implies that the electrically isolated electrode (and atleast one other electrode) is making good contact. A high impedancereading implies that either the electrically isolated electrode (and/orall of the electrically common electrodes) is making poor contact. Otherimpedance measuring algorithms can also identify poorly contactingelectrodes. The only distinction that cannot be made by such an approachis the correct identification of a single electrode making good contact,when all of the remaining electrodes are making poor contact.

The medical professional may work around a poorly contacting electrodeif he feels that a properly contacting adjacent electrode will make areasonable substitute. For example, if the 6 electrode is found to bemaking poor contact, the MP may elect to defibrillate using the α-εpair, instead of the standard α-6δ pair. Alternatively, the MP may askthe enabler to apply pressure over the surface of the δ electrode,perhaps using a circular motion, in order to achieve better δ electrodecontact.

Combinations of two or more electrodes may also be used to apply a lowervoltage energy to the victim's torso for pacing the heart. The medicalprofessional would select the choice of electrodes in the same way thathe selects the defibrillating electrodes. The choice of pacingelectrodes need not be the same as the choice of defibrillatingelectrodes.

Table 3 shows how combinations of two or more electrodes may be used torecord seven of the twelve standard electrocardiogram leads.

TABLE 3 ECG Recording Configuration on Five Electrode Pad Lead Electrode#1 Electrode #2 I α β II α δ III β γ aVR α β + γ aVL β α + γ aVF γ α + βV3/V4 δ α + β + γ V6 ε α + β + γAn eighth configuration, listed in the table as V3/V4 records acomposite of the standard lead V3 and lead V4, because of the large sizeof the δ electrode. Furthermore, the medical professional may elect torecord between any combination of electrodes, giving him, in principle,a total of 90 recording options.

Different numbers, shapes and locations of large electrodes couldaccomplish the tasks of defibrillation, pacing, ECG monitoring andmonitoring of appropriate pad contact.

Element 204B in FIG. 5B is a modified version of the standard electrodepad 204A. In addition to the five defibrillating electrodes, it containsmultiple smaller electrodes 240 (F), 242 (G), 244 (H), 246 (J), 248 (K),250 (L) and 252 (M). Table 4 shows how combinations of these electrodescould be used to record 10 of the 12 leads of a standardelectrocardiogram.

TABLE 4 ECG Recording Configuration on Five Electrode Pad with SevenSensing Electrodes Lead Electrode #1 Electrode #2 I F G II F K III G JaVR F G + J aVL G F + J aVF J F + G V1 H F + G + J V3/V4 δ F + G + J V5K F + G + J V6 ε F + G + JElectrode 250 (L), though not situated at one of the standardelectrocardiogram lead locations, may nevertheless be of value to themedical professional. The non-victim side of the pad is shown in FIG.5B. The conductive surface of each of the ECG electrodes faces theopposite or victim side of the pad. A wire extends from each ofelectrodes 240-252. These wires coalesce to form cable 213, which alsocontains the five wires extending from the five defibrillatingelectrodes.

Impedance measurements involving combinations of the seven smallelectrodes may be utilized to identify poorly contacting electrodes,using an algorithm similar to that described for the large electrodes.Alternatively, an algorithm involving impedance measurements betweencombinations of large and small electrodes could be utilized. The onlyadvantage of this latter algorithm is that in cases where only one largeand only one small electrode are making proper contact, it couldidentify which are the properly contacting ones. The algorithm whichuses only the five large electrodes, and the algorithm which uses onlythe seven small ones would fail to identify the properly contactingones, in circumstances in which only one large and one small electrodeare making proper contact.

An improperly contacting small electrode may indicate that part of anadjacent large electrode is making poor contact. This would be usefulinformation, since partial non-contact of a large electrode would bemore difficult to diagnose from impedance measurements and since partialnon-contact could reduce the chance of defibrillation success. If, forexample, all impedance measurements are low except that betweenelectrode L and the composite of F/G/H/J/K/M, it would imply that thearea of poor pad contact might extend beyond small electrode L to largeelectrode ε. If electrode ε was going to be used for defibrillation, theMP would then ask the enabler to apply pressure over electrodes L and ε,in order to establish better contact between these electrodes and theskin surface.

Different numbers, shapes and locations of small and/or large electrodescould accomplish the tasks of defibrillation, pacing, ECG monitoring andmonitoring of appropriate pad contact.

Element 206 in FIG. 5C is a modified version of the electrode pad 204B.The lower perimeter, i.e. the perimeter adjacent to electrodes J, I, H,δ and K has been modified to curve upwards to exclude a region overlyingthe breasts of a female victim. The purpose of the modification is toassure better electrode contact for female victims. The pad is shaped sothat at least some breast tissue would lie caudal to the pad, i.e.between the pad and the victim's feet. The breast tissue would therebynot prevent the γ and the δ pads from making proper contact. Pad 206contains an elliptically shaped β electrode 254, which allows forrostral displacement of the δ electrode, i.e. towards the victim's head,to accommodate breast tissue. The γ electrode 256 is also elliptical inshape, to allow some of the tissue of a female victim's right breast tolie outside of the perimeter of the pad. The ε electrode 259 is similarin shape and position to its counterpart, element 239 in the unmodifiedversion of this pad shown in FIG. 5B.

In all other aspects the properties and operation of pad 206 are similarto pad 204B.

Modifications of pad 206 are possible including modification in theshape of any electrode, modifications in which the β and γ electrodesare omitted, modifications in which the long axis of either of the β orγ electrodes is not horizontally oriented, and modifications in whichthe center of the δ electrode is displaced in either the rostral,caudal, right or left directions. Modifications are also possible inwhich the size of the α electrode 253 and the δ electrode 258 aresmaller than their counterparts in non-concave electrode pad.Modifications are also possible in which the shape of the caudalsurface, though concave, differs from that shown in FIG. 5C.

Other modifications of pad 206 are possible in which different numbersand locations of small and/or large electrodes could accomplish thetasks of defibrillation, pacing, ECG monitoring and monitoring ofappropriate pad contact.

Modifications of pad 206 are possible which do not contain the sevensmall ECG electrodes In this case, its operation would be similar to pad204A.

FIG. 5D shows a view of pad 204B from the side opposite that shown inFIG. 5B. A portion of the protective backing 260 has been peeled off andpartially folded. Removing the backing, a procedure performed by theenabler under the direction of the medical professional, exposes theconductive surface of the electrodes as well as an adhesive surface 262.The adhesive surface holds the pad and its electrodes onto the victim'schest, after the pad has been initially placed there by the enabler.

FIG. 5E shows an edge view of pad 204B, with a view toward the edgewhich is to be applied to the victim's right. Electrodes 240, 231, 244,235 and 246, are seen in profile. The electrodes protrude from anon-conductive semi-rigid supporting material 264. A conductive strip266 is attached to backing 260, and extends from electrode 231 to 244.Conductive strip 266 maintains a low resistance path between electrodes231 and 244 while the backing is in place. The MP can determine when theenabler has removed the backing, by observing a sudden rise in theresistance of this path. Strip 266 can extend between any two adjacentelectrodes.

In an alternative embodiment, the strip would touch each of two smallconductive areas adhering to supporting material 264, which are not ECGelectrodes, but which are conductive surfaces dedicated exclusively toallowing the assessment of contact between the backing and the pad. Thisapproach avoids the placement of conductive additional conductivematerial in contact with the ECG electrode gel. One wire would extendfrom each of these conductive surfaces to join cable 213, FIG. 5B.

In another alternative embodiment, a conductive strip is attached to onepoint on the surface of supporting material 264, runs along the surfaceof backing material 266, and, at its other end, is attached to anotherpoint on the surface of supporting material 264. Each of the twoattachment points on 264 is electrically in contact with a wire whichgoes on to form part of cable 213. When the enabler pulls off thebacking material, the conductive strip is broken, terminating electricalcontinuity between the wires at the two ends of the strip.

Edge and back views of pads 204A and 206 show features analogous tothose seen in FIG. 5E, showing the side view of pad 204B.

3.3 Matrix Electrode Pad

FIG. 5F shows another type of multi-electrode pad 208, hereinafterreferred to as a matrix electrode pad. One group of electrodes issituated to contact the upper right side of the victim's chest. Anothergroup of electrodes is situated to contact the left side of the victim'schest, beneath the breast. Additional electrodes lie on a strip whichextends diagonally between the two aforementioned groups of electrodes.

The large number of closely spaced electrodes in the upper right andlower left groups allows the MP to “construct” composite defibrillatingand pacing electrodes of desired shape and location by rendering each ofa number of adjacent small electrodes electrically common. Theelectrodes are made electrically common within the portable unit,following the commands of the medical professional.

In the embodiment shown in FIG. 5F, thirty electrodes, 268 are eachdesignated by a unique column label (using letters A through K) and rowlabel (using numerals 1 through 3). Thus, the electrode which, on thevictim, is most rightward and most rostral is designated as A1, whilethe electrode which is most leftward and caudal is designated as K3.Actual row and column labels may be printed on the non-victim side ofthe pad. Two additional electrodes, 270 and 272 are situated on thediagonal strip which connects the right and left sections of the pad.They are designated V₁ and V₂, labels which are consistent with 12 leadECG designations.

When using the pad to defibrillate or pace a victim, the medicalprofessional 301 would construct a composite electrode by commanding theportable unit 104 to make a group of electrodes electrically common. Forexample, the nine electrodes A1-A3, B1-B3 and C1-C3 form a three bythree array which could serve as the right chest electrode, analogous tothe a electrode 230 on the five electrode pad 204A, FIG. 5A.

If instead of selecting the electrodes in columns A, B and C, the MPselects the nine electrodes in columns B, C and D, he has effectively“moved” or shifted the location of the right chest electrode toward themidline of the chest. If he wishes to use a larger right chestelectrode, he could select all twelve of the electrodes in columns A, B,C and D. If he wishes to use a smaller right chest electrode he couldselect a two by two array, e.g. A1, A2, B1 and B2; a two by three array,e.g. A1, A2, A3, B1, B2 and B3; or an irregularly shaped array, e.g. A1,A2, A3, B1 and B2. He could select a single electrode, or he couldselect a non-contiguous group of electrodes. Thus any combination of thetwelve right sided electrodes could form the right chest electrode.

The left chest electrode is selected in a manner similar to that for theright chest electrode. For example, the nine electrodes in columns G, Hand J would be a typical choice. If the MP wished to “move” or shift theleft chest electrode further leftwards, he could select the nineelectrodes in columns H, J and K. If the MP desired a more rightwardslocation, the electrodes in columns F, G and H could be selected. As isthe case with the right chest electrode combination, any combination ofleft sided electrode(s) could constitute the composite left electrode.

Electrocardiogram recording is accomplished by utilizing two or more ofthe thirty two electrodes, as described in Table 5.

TABLE 5 ECG Recording Configuration on Thirty Two Electrode Pad LeadElectrode #1 Electrode #2 I-like A3 K1 II D1 E3 V1 V1 A1 + A3 + C1 +E3 + G3 + J3 V2 V2 A1 + A3 + C1 + E3 + G3 + J3 V3 E1 A1 + A3 + C1 + E3 +G3 + J3 V4 F1 A1 + A3 + C1 + E3 + G3 + J3 V5 H1 A1 + A3 + C1 + E3 + G3 +J3 V6 K1 A1 + A3 + C1 + E3 + G3 + J3Because of this pad's diagonal orientation, certain modifications inrecording technique are required. The absence of electrodes in thevicinity of the left arm results in inability to display lead III andthe three augmented leads. Lead I is recorded from the pair ofelectrodes which are closest to horizontal on the pad. However, thegeometry of the pad may result in inability to achieve a perfectlyhorizontal orientation; hence Table 4 refers to this lead as “I-like.”Similarly, the ordinarily horizontal relationship of leads V₁ and V₂might be modified to accommodate the diagonal region of the pad. Theelectric potential at the six V leads, ordinarily subtracted from thatof a composite of right arm, left arm and leg, is in this casesubtracted from a modified composite consisting of electrodes A1, A3,C1, E3, G3 and J3. Other electrode combinations than those listed inTable 5 could be used, if, at the MP's discretion, the medical situationcalled for such an analysis.

The electrode combination used to defibrillate a victim may be differentthan the electrode combination used for pacing, which in turn may bedifferent from the combinations used for ECG recording.

As described above in connection with the pads containing fivedefibrillating/pacing electrodes (FIGS. 5A and 5B), in the event thatone or more electrodes in the matrix pad 208 is making poor contact withthe patient, the MP can identify the poorly contacting electrode(s) andcan either work around it or ask the enabler to correct the condition.Circuitry within the PU performs impedance measurements betweenelectrode combinations to identify poorly contacting electrode(s). Foreach measurement, one electrode is electrically isolated, and the otherthirty one electrodes are electrically common, in a manner similar tothat described for the aforementioned pads. For example, the MP wouldknow that electrode D3 is making poor contact if the impedancemeasurement of D3 vs. an electrically common composite of the other 31electrodes, is high, while the impedance value of other combinations ofelectrodes is low The medical professional may work around a poorlycontacting electrode if he feels that a properly contacting adjacentelectrode will make a reasonable substitute. Alternatively, the MP mayask the enabler to apply pressure over the surface of the poorlycontacting electrode, in order to achieve better electrode contact.

Different numbers, shapes, sizes and locations of electrodes couldaccomplish the tasks of defibrillation, pacing, ECG monitoring andmonitoring of appropriate pad contact. The shape of the pad and thelength of the diagonal region is preferably designed to fit the averagesize person. The electrodes themselves need not be of uniform size orshape, and the inter-electrode distance need not be uniform.

The back of the pad is constructed in a manner similar to that shown inFIG. 5E. The conductive strip allowing the monitoring of backing removalextends between any two adjacent electrodes.

3.4 Single Electrode Pads

Another approach to electrode pads is the placement of two or moresingle electrode defibrillator/pacing pads, as are known in the art,upon the torso. In the embodiment shown in FIG. 5G, three singleelectrode pads, 210, are in place on the torso. A greater or lessernumber of these single electrode pads may be used. (Four pads shown inFIG. 7B.) These single electrode defibrillator/pacing pads are availablein the tool-kit section of the Portable Unit, as described above inconnection with FIG. 7B. The pads are distinguished from each other bythe presence of a numeral on the non-victim surface of the pad, bycolor, by shape or by more than one such feature. The medicalprofessional instructs the enabler in the proper location of eachelectrode as described previously

A wire, 216, extends from each pad leading to universal connector, typeD, 218D.

Standard operating procedure for defibrillation calls for the passage ofan electric current between two pads on the victim's chest, one placedhigh on the chest to the right of the midline, and one placed on the farleft side of the chest, beneath the nipple. Alternate approaches involvea single electrode on the chest surface (generally referred to asanterior) and another electrode on the back (generally referred to asposterior), indicated by dashed lines. FIG. 5G shows the placement oftwo anterior electrodes (labeled “1” and “2” on the pads) and oneposterior electrode (labeled “3” on the pad). The posterior placement isindicated in the figure by dashed lines. By placing more than twoelectrode pads on the torso, the medical professional has options beyondthose available for the two electrode approach. These include: a) theability to repeat defibrillation using a different combination ofelectrodes if a first attempt fails; b) the ability to applydefibrillating energy simultaneously between more than two electrodes(For example, in FIG. 5G, energy could be applied between pad 1 and pad2, and between pad 1 and pad 3, simultaneously. Furthermore, thissimultaneous application need not involve the same voltage or waveformbetween the different pairs of electrodes.); and c) the ability to applyenergy to different pairs non-simultaneously.

The single electrode pads may be used for defibrillation, for pacingand/or for recording the electrocardiogram. Any number, shape and sizeof electrode pads may be utilized; and they need not be of uniform shapeor size. Their location may be anywhere on the body, in accordance withproper medical practice.

4. Sample Cardiac Arrest and System Operation 4.1 Overview of SampleArrest

For illustrative purposes, an hypothetical cardiac arrest is discussed.The seven major phases of the events during the hypothetical cardiacarrest are described in Table 6:

TABLE 6 Seven Phases of Activity During a Cardiac Arrest Phase Time(m:ss) Activity 1 0:00-0:31 Initial enabler action from the time hefirst sees victim until button press (activation of the PU by theenabler) 2 0:31-0:50 A series of four “handshakes” between the MP andthe enabler: a) communication, b) telemetry c) audio, and d)informational 3 0:50-2:19 Transport of PU from pre-arrest location tovictim's side; setup of PU at victim's side; four layer handshakebetween victim MP, including diagnosis of ventricular fibrillation 42:19-3:18 MP treats victim: a) first shock b) second shock c) firstpacing d) second pacing; Treatment causes normalization Of heart rhythm5 3:18-7:25 CPR, if necessary; victim identification; victim dataretrieval; tracking and waiting for the emergency medical team (EMT) 67:25-7:43 A series of four handshakes between the MP and the EMT 77:43-variable MP transfers control of PU to EMT; MP advises EMT; MPguides enabler in replacement of PU

4.1.1 Phase One: Initial Enabler Action

The start time, the moment when the enabler 100 first observes theVictim 102, a person who has suffered a cardiac arrest due toventricular fibrillation, is arbitrarily designated with a time of 0:00.This marks the start of phase one. Nearly all of phase one, which endswhen enabler presses the emergency button 106, is the time for theenabler to move from the victim to the portable unit 104.

4.1.2 Phase Two: Handshakes Linking Enabler and MP

Phase two involves a consecutive series of four handshakes, each oneconfirming a progressively broader link between the enabler and themedical professional.

4.1.2.1 Role Played By Handshakes; Relationship Between Handshakes andBackups; Relationship Between Handshakes and Links

The handshakes play an important role in the operation of the system.Since decision making, when performed by the MP, occurs in a locationseparated from the emergency scene, it is essential that the MP know atall times if his link with the PU is robust. And it is vital that if theMP believes that his link with the PU is not robust, he can takecorrective action by: a) directing the PU, the SU or CS to remedy orrestore the link; and/or b) directing the PU to switch its guidance fromMP-based, to an onboard guidance system, the AED/P (by directing the PUto enter Master Control State 2). It is equally vital that the PU can,at all times evaluate the ongoing link with the MP; and that the PU can,if it recognizes that the link with the MP is not robust, takecorrective action by: a) attempting PU-based or SU-based maneuvers toremedy or restore the link; and/or b) switch its guidance from MP-based,to an onboard guidance system, the AED/P (by itself entering MasterControl State 2, without the necessity of the MP for this transition).Accordingly, preferred embodiments of this invention provide means forimplementing one or more layers of “handshake” (HS). And preferredembodiments of this invention provide means for implementing theaforementioned corrective actions, with one or more levels of backup, inthe event of handshake failure.

In a preferred embodiment of the invention, each handshake after thefirst one builds on the previous handshake, by either expanding theroute over which information exchange is confirmed, or by adding a morecomplex form of information exchange. The four handshakes of thisembodiment may therefore be conceptualized as being layered, each on topof the previous one. The execution of all four handshakes confirms theintegrity of a link (see Appendix 2). The four handshakes linking the ENand the MP are summarized in table 7, below.

TABLE 7 Four Layers of Handshake Linking Enabler and MP Layer HandshakeBackup Backup Backup # Type Between #1 #2 #3 1 Communi- PU & CS Δ routeΔ mode MC = 2 cation 2 Data/ PU & CS Δ coding Δ HS MC = 2 Commands 3Audio 3A MP to EN EN & MP Headset Voice Pr Text Pr 3B EN to MP EN & MPHeadset Keyboard SpeechRec 4 Informa- EN & MP Interp'r FoLanRec VideoCAM tional

Embodiments of the invention with a greater or lesser number ofhandshakes are possible. Embodiments of the invention in which two ormore of the aforementioned handshakes are merged are also possible.Embodiments of the invention in which one of the aforementioned layersis sub-divided into multiple layers are possible. Embodiments of theinvention in which some or all of the handshakes are not layered, eachon top of the previous one, are possible. Embodiments of the inventionin which other links (e.g. the Victim-MP link, or the EMT-MP link) havea different number of handshakes or a different handshake format arealso possible.

4.1.2.2 Backup Systems for a Failed Handshake

For each HS, three levels of backup are listed. Embodiments of theinvention with a larger or smaller number of backups are possible.Embodiments of the invention are possible which use the same backupslisted in Table 7, but utilize them in a different order. Embodiments ofthe invention with different backup systems are possible.

Referring to Table 7, for the first two layers of HS, backup #1 andbackup #2 are maneuvers which attempt to remedy or restore a less thanadequate or interrupted handshake. The third level of backup for thelayer #1 and layer #2 handshakes, PU self-programming to Master ControlState 2, transfers control of the PU to the AED/P 128, the automaticcircuitry which lets the PU function without a link to the centralstation. Another group of backup options for these two layers, notlisted in the table, includes the substitution of a redundant hardwareunit for a failed one (by electronic means), once the failure has beenlocated. Yet another option is the manipulation of antenna size,orientation, location, number or shape. Hardware substitution andantenna manipulation may involve the PU, the SU and/or the centralstation. Backup systems for failed handshakes are discussed in detail,below.

The AED/P is not likely to be necessary for backing up the third andfourth layers of HS (see below). There are a variety of communicationsenhancing features (see Table 7 and the text below) which perform thebackup functions for layers #3 and #4 of the enabler-MP link.

4.1.2.3 Four Handshakes which Link the Enabler and the MP

4.1.2.3.1 The Communication Handshake

When the enabler presses the emergency button, the first of thehandshakes, a communication handshake, is established between theportable unit and the central station. This handshake is described indetail below in connection with FIG. 12. It continuously lets the PUknow that the CS is receiving PU signals and responding properly, whilesimultaneously letting the CS know that the PU is receiving CS signalsand responding properly.

The handshake involves the transmission of signals over a route that mayinclude, in succession:

a) the PU microprocessor (which first receives the “button press”signal);

b) the PU encoder;

c) the PU transmitter;

d) the CS receiver;

e) the CS decoder;

f) the CS microprocessor

g) the CS encoder;

h) the CS transmitter;

i) the PU receiver; and

j) the PU decoder.

The PU decoder then sends a signal to the PU microprocessor, completesthe first cycle around this loop. Activation of the PU microprocessoralso may thus be considered to mark the first step of the second cycleof what is a continuous set of cycles for the entire duration of thehandshake. Any time a microprocessor fails to receive the appropriatesignal, it initiates the transmission of alternate signals to reflectits altered input (see below and Table 16). If the PU microprocessorreceives signals indicating a handshake failure, it may initiate actionswhich activate one the backup systems listed in Table 7. If thehandshake is unsuccessful, despite multiple attempts using multiplecommunication routes and modalities, the microprocessor will cause thePU to switch to Master Control State 2, and thereby: a) hand control ofdefibrillation and pacing over to the automatic externaldefibrillator/pacer (AED/P) control logic; and b) enable lock release ofthe PU from the SU (such that MP “approval” of the release is no longernecessary).

Embodiments of the invention are possible in which the communicationshandshake involves either a greater or a smaller number of componentsthan the ten listed above as (a) through (j). Embodiments of theinvention are possible in which there is only a one-way handshake, e.g.by having the PU receive a continuously transmitted CS signal, and byhaving the PU microprocessor react to the absence of such a signal bycausing backup measures to be instituted.

When the SU is part of an attempted PU-CS link, the ten item list ((a)through (j) above) is modified to allow for a PU-SU communicationhandshake and a SU-CS communication handshake (see Sections 4.1.2.4.1,4.1.2.4.5 and Table 16) Such handshakes would test the SU transmittersand receivers and the SU microprocessor.

4.1.2.3.2 The Data/Commands Handshake

Once the communication handshake is established, a data and commandhandshake follows. The data/commands handshake cannot occur unless thecommunication handshake is running continuously in the background. Thissecond layer handshake lets the MP know: a) that data from the PU can betransmitted from the PU and received by the CS; and b) that commands canbe transmitted from the CS, and can be received and executed by the PU.

The handshake involves the transmission of signals over a route thatincludes, in succession:

a) the CS processing input;

b) the CS encoder;

c) the CS communications output;

d) the PU communications input;

e) the PU decoder

f) the PU processing output

g) the PU processing input;

h) the PU encoder;

i) the PU communications output;

j) the CS communications input;

k) the CS decoder;

l) the CS processing output;

The CS and the PU microprocessors may be involved at multiple pointsalong this sequence (see ahead). This handshake may be initiated by anaudio signal or sound at the CS. Alternatively it may be initiated by anon-audio command at the CS such as a signal to the PU to send a testECG. The aforementioned involve two-way handshakes. Alternative methodsof handshaking could involve one-way handshakes which may includecontinuously or intermittently emitted test signals from either the PUor the CS end.

This data/commands handshake traverses a wider loop than does thecommunication handshake. A completed data/commands handshake confirmsthe proper functioning of: a) all of the components included in thecommunication handshake; b) the CS processing (which includes audio andnon audio) input and output components, and the PU processing input andoutput components; and c) other components which may be involved in testcommands and test signals.

The data/commands handshake may be repeated to confirm the properexecution of each of multiple test commands, or the proper transmissionof each of multiple test signals. Alternatively these commands andsignals may traverse the system simultaneously. The data/commandshandshake may be repeated continuously, intermittently or performed justonce during a particular medical emergency (see Section 5.).

Embodiments of the invention are possible in which the data/commandshandshake involves either a greater or a smaller number of componentsthan those referred to above. Embodiments of the invention are possiblein which there are one or more different one-way and/or one or moredifferent two-way data/commands handshakes.

When the SU is part of an attempted PU-CS link, the routine is modifiedto allow for a PU-SU data/commands handshake and a SU-CS data/commandshandshake (see Sections 4.1.2.4.1, 4.1.2.4.5 and Table 16). Suchhandshakes would further evaluate the SU transmitters and receivers andthe SU microprocessor.

If the layer two handshake is unsuccessful, despite the first two backupapproaches (listed in Table 7 and discussed below), then PU entry intoMaster Control State 2, with resultant enabling of AED/P logic and lockrelease, is the third level backup approach, as was the case with anunsuccessful communication handshake. After the layer two handshake iscomplete, the successful transmission and execution of commands isdocumented by a series of confirmation signals described below;Unsuccessful transmission or execution of individual commands isdocumented by a series of error signals described below.

Both the communication and the data handshakes may be established veryquickly, i.e. within a time interval on the order of one second or less.

4.1.2.3.3 The Audio Handshake

After establishment of the data and command handshake, the ability toexchange audio is established during the third layer of handshake. TheMP must determine that he can hear the enabler clearly and that theenabler can hear him clearly. Most of the time, any difficulty in thisarea will be easily remedied (by the MP or by the system) by adjustingan amplifier gain control, or by adjusting another signal conditioningparameter at either the PU or the CS end.

The audio handshake traverses a wider loop than does the data/commandshandshake. This handshake involves the proper passage of informationamong: a) the twelve data/commands items listed as (a) through (1) inSection 4.1.2.3.2, above; and b) the enabler and the medicalprofessional. Their ability to hear each other involves: a) the properfunctioning of the aforementioned twelve items; b) the enabler's abilityto adequately hear the audio output of either the PU speakers 146, orthe PU handset 150; and c) the MP's ability to properly hear the voiceof the enabler, picked up by either PU microphone 148 or PU handset 150.(It is assumed that the speakers, microphones, handsets and/or headsetsat the central station can be reliably used and optimized by the MP.)

When the SU is part of the PU-CS link, a suboptimal audio response maybe remedied (by the MP or by the system) by the adjustment of a SUamplifier gain control, or by the adjustment of another signalconditioning parameter among the SU receivers and transmitters, inaddition to such adjustments at either the PU or the CS end.

The backups for this third layer are devices or techniques intended tosupport a marginally functioning audio system. They include:

a) EN using PU handset 150 or headset 168;

b) MP triggering of voice prompts (Voice Pr) which have beenpre-recorded and stored in the PU;

c) MP sending text messages (Text Pr) which appear on one of the PUscreens 156;

d) EN using a virtual keyboard displayed on one of the touch sensitivescreens, 156, of the PU; and

e) MP using a speech recognition program (SpeechRec) within the PU.

In the event of the enabler not hearing the MP properly, techniques (a),(b) and (c), above, would be used. In the event of MP not hearing theenabler properly, techniques (a), (d) and (e), above, would be used. Thedetailed algorithm for this is discussed below.

There is little or no need for AED/P backup for the third layer ofhandshake. The reason is as follows. With a successful second layer ofHS, it has been established that data can flow from PU to CS, andcommands may be transmitted to and executed by the PU. If EN can nothear MP directly, then either a) voice or text prompts are recognized bythe EN, in which case the MP can proceed to deal with the emergency, infull control of the PU, and able to communicate indirectly with theenabler, or b) voice or text prompts are not recognized by the enabler,in which case an AED would not be likely to function either.

4.1.2.3.4 The Informational Handshake

The fourth layer of handshake is an informational one. Nine seconds areslotted, starting at 0:41 for the MP to request and receive adescription of the medical emergency. During and immediately followingthe description, the MP decides if the event being described is one inwhich the PU can be used to help the victim. Backup systems include aninterpreter (Interp'r) or a foreign language recognition program(FoLanRec) to deal with a foreign language speaking enabler, and a videocamera (Video CAM) to help distinguish a bona fide enabler from apotential prankster. Since this fourth layer of handshake establishesthe appropriateness of the medical emergency and of the enabler, AED/Pbackup is not appropriate for this layer.

This handshake involves a more complex form of information exchange thanthat of the audio handshake. Since the informational handshake dealswith cognitive issues (viz. the victim diagnosis) it does not involveany additional communication or audio equipment.

4.1.2.4 Role of the Stationary Unit in the Handshake Protocol

The discussion up to now has not addressed the distinction between a“direct PU-CS link” (i.e. a link between the PU and the CS in whichinformation does not pass through the SU), and an “indirect PU-CS link”(in which the PU-CS link is the composite of a PU-SU segment [whereininformation passes between the PU and the SU] and a SU-CS segment[wherein information passes between the SU and the CS]). Either a directPU-CS link or an indirect PU-CS link must be established. Thisdistinction in routing will now be addressed.

4.1.2.4.1 Single Direct Link Between PU and CS as the Default RoutingApproach; Stationary Unit Functions as a Backup

Conceptually, the simplest approach to a PU-CS link is one in whichbutton press results in the attempted establishment of a direct PU-CScommunication link. With such a link, information is sent from the PU tothe CS without passing through the SU, and information and commands aresent from the CS to the PU without passing through the SU; Thecommunication in this approach is “wireless.”

“Wireless,” hereinabove and hereinbelow, refers to communicationswithout a material connection between the two communicating units; suchas communication methods employing radio frequency or infrared signalcarriers. “Wire,” hereinabove and hereinbelow, refers to communicationswith a material connection between the two communicating units; such ascopper, other metal or optical fiber connections. A wireless connectionmay include multiple segments, some of which use wire.

Table 8 and the discussion which follows in this Section and in Section4.1.2.4.2 address the backup approaches available in the event of afailure in any segment of the PU-CS link, when there is a SU availableor involved. “Segment” is hereinabove and hereinbelow defined as aspatially distinct portion of a link, such that the composite effect ofall of the segments constitutes the effect of the entire link. Thus thePU-SU segment plus the SU-CS segment constitute the PU-CS (or PU-SU-CS)link. The second through fifth columns of the table refer to eachpossible segment or link between the PU and the CS. Within Section4.1.2.4, the term “connection” refers to the physical aspect of asegment, and is used nearly synonymously with “segment.” In the table,“PU-SU wire” refers to the connection between the PU and the SU viaconnectors 188 and 190; “PU-SU Wireless” refers to a wireless connectionbetween the PU and the SU. In the analysis which follows in Sections4.1.2.4.1 through 4.1.2.4.4, a link or segment is assumed to beestablished when the first two layers of handshake, i.e. communications(see Section 4.1.2.3.1) and data/commands (see Section 4.1.2.3.2) areestablished. This is further discussed in Section 4.1.2.4.5, below.

TABLE 8 PU-CS Routing Analysis and Backup When SU is Available PU-SUState PU-SU Wire- Backup Backup Backup # Wire less SU-CS PU-CS #1 #2 #31 Any Any Any + Communication Intact 2 Any + + − Communication Intact3 + − + − PU-176 PU-176 MC = 2 to SU to CS 4 − − + − MC = 2 PU-176 to CS5 Any Any − − MC = 2 PU-176 to CS Key + = communication intact betweenindicated units − = communication not intact between indicated units Any= + or −, i.e. communication may or may not be intact between indicatedunits PU-176 to CS = enabler uses PU wire/jack 176 to connect PU toTelco, i.e. the public telephone network PU-176 to SU = enabler uses PUwire/jack 176 to connect PU to SU MC = 2 = Master Control State 2

In this format (i.e. primary attempt is a direct PU-CS link), only if awireless link between the PU and the CS could not be established (States#2-#5 in Table 8), would the stationary unit become a unit of thecommunication chain. In such a situation the backup would involve tryingto establish an indirect PU-CS link (i.e. via the SU) The sequence ofevents could be:

a) button press;

b) attempt to establish a direct PU-CS link fails;

c) the PU, over its connection to the SU via connectors 188 and 190,causes the SU to attempt to establish a connection with the CS;

d) the SU establishes a connection with the CS; the PU-CS link is thencomplete since PU is already connected to SU via connectors 188 and 190;the enabler and the MP can now communicate; and

e) the PU then attempts to establish a wireless connection with the SU.

Once step (d) is completed, the exchange of vital information betweenthe enabler and the MP can begin (via the wire connection between the PUand the SU), while the system attempts to establish a wirelessconnection between the PU and the SU. If the attempt (step (e), above)is successful, a proper wireless PU-CS link will have been established,and the PU is ready for detachment from the SU, if the MP decides thatthe detachment is necessary (based on the enabler's description of themedical emergency).

The attempted two-segment link between PU and CS can only succeed ifboth segments, the PU-SU segment, and the SU-CS segment can beestablished. Section 4.1.2.4.1.1 refers to the situation when: a) bothsegments can be established; but b) one (but not both) of the PU-SUforms of connection (wire and wireless) can not be established. Section4.1.2.4.1.2 refers to the situation when one or both of the PU-SUsegment and the SU-CS segment can not be established.

4.1.2.4.1.1 Direct PU-CS Link Can Not Be Established; Failure of One ButNot Both Possible PU-SU Connections; Successful SU-CS Connection

The PU-SU segment can be initially established with either a wire orwireless PU-SU connection.

If the direct connection between the PU and the SU via connectors 188and 190 is not intact, the PU may attempt to contact the SU via awireless route. If the PU-SU wireless route is established, and if it isfollowed by the establishment of a SU-CS connection (State #2, Table 8),a proper PU-CS link will have been established. State #5 (see Table 8),in which the PU-SU wireless route is established but the SU-CSconnection can not be established is discussed below in Section4.1.2.4.1.2

If a wireless PU-SU connection can not be established, but the wireconnection via connectors 188 and 190 is intact, and a SU-CS connectionhas been established, (State #3, Table 8), the enabler and the MP cancommunicate only if the PU remains attached to the SU. In thissituation, the enabler is advised by the MP of a number of optionsincluding:

a) the option to plug the telephone wire/male jack 176 (from the PUtool-kit) into the female telephone jack 155 of the SU, and thereby tooperate the PU with a wire connection to the SU;

b) the option to use both the wire/jack 176 and an extension wire(located within the PU tool-kit) in tandem, if the wire/jack 176 is notlikely to be of sufficient length to reach from the SU to the locationwhere the PU must be placed in proximity to the victim;

c) the option to transport the PU to the victim (if certainvictim-related criteria have been met):

-   -   (i) Prior to removal of the PU form the SU (and thereby        terminating enabler-MP audio contact), the MP instructs the        enabler about upcoming procedures and about how the enabler may        interact with the AED/P; He also instructs the enabler that they        may be able to resume their communication once the PU has been        moved to a location near the victim, either by wireless means,        or by having the enabler then plug wire/jack 176 (with or        without extension) into a female jack of the public telephone        network.    -   (ii) After properly instructing the enabler, the MP may then        give a command to the PU to enter Master Control State 2.    -   (iii) Enabler then detaches the PU from the SU and transports it        to the victim;    -   (iv) During transport the PU and the CS will attempt to contact        each other; if contact is successful, the enabler-MP interaction        proceeds as described hereinabove and hereinbelow;    -   (v) if contact is unsuccessful through the time that enabler        arrives at the victim's side, the enabler has the options of        either plugging the telephone wire/jack 176 directly (or via the        extension) into the public telephone network, or of continuing        to use the PU in its AED/P backup mode. The enabler is reminded        of these options and of associated details via voice prompts.

There a multiple possible variations in the timing of the setup of thewireless version of the PU-SU connection: a) the PU-SU connection couldbe wireless from the beginning, i.e. from the time of button press; b)the PU-SU connection could initially be via connectors 188 and 190, butattempts to establish a wireless PU-SU connection could proceed before,or at the same time as the attempt to establish the SU-CS connection(rather than first establishing the SU-CS connection, as is the scenariodescribed in Section 4.1.2.4.1). If, using one of these variations, thePU-CS link fails to be established, the backups include: a) attemptingto use a wire connection for the PU-CS link; b) attempting to use a wireconnection for the PU-SU segment; c) AED/P backup (described below inSection 4.1.2.4.1.2).

4.1.2.4.1.2 Direct PU-CS Link Can Not Be Established; Failure of BothPossible PU-SU Connections and/or Failure of SU-CS Connection

If the direct PU-CS link has failed, then communication between theenabler and the MP can not occur unless an indirect PU-CS link can beestablished. The indirect link can not be established if: a) neither awire nor a wireless connection between the PU and the SU can beestablished (State #4, Table 8); or b) a SU-CS connection can not beestablished (State #5, Table 8). In either of these two situations, thesystem must switch to the AED/P backup. The scenario could be:

a) The PU switches to Master Control State 2.

b) The PU then issues voice prompts directing the enabler to remove thePU and transport it to the victim's side, if certain victim-relatedcriteria are met (see below).

c) The enabler then detaches the PU from the SU and transports it to thevictim.

d) From this point in time onwards, the PU will make periodic attemptsto communicate directly with the CS. If such an attempt is successful,then the enabler-MP interaction may take place as is describedhereinabove and hereinbelow.

e) If the PU does not make contact with the CS by the time the PU isplaced next to the victim (sensor switches 178 signaling placement ofthe PU), a voice prompt then tells the enabler that he has two options.The enabler may select option (i), and then go to option (ii) if option(i) is unsuccessful, or may select option (ii) initially:

-   -   (i) to extend telephone wire/male jack 176 (with or without the        extension) from the PU tool-kit to connect to a female jack of        the public telephone network; and after sensing such connection        the PU will attempt to establish a link with the CS; if the        attempt is successful, then the enabler-MP interaction takes        place as described hereinabove and hereinbelow; if the attempt        is unsuccessful, the enabler proceeds with option (ii) (which        follows hereinbelow);    -   (ii) to use the PU as an automatic external defibrillator; the        PU will then further instruct the enabler via voice prompts.

It is highly unlikely that a SU-CS connection would not be able to beestablished, since: a) there are many possible routes including thepublic telephone network, the internet, private communications networks,or combinations of these; and b) the ability to establish the SU-CSconnection would be examined and assured at the time that the SU isinitially set up, and at other times when diagnostic checking isperformed (see below). It is also highly unlikely that neither form ofPU-SU connection would be able to be established, for the same twoaforementioned reasons regarding the likelihood of being able toestablish a proper SU-CS connection.

4.1.2.4.2 Two Connections: One from PU to SU and One SU to CS as theDefault Routing Approach

In a preferred embodiment of the invention, a portable unit would bewired directly to the SU via connectors 188 of the PU (FIG. 8) and 190of the SU, and a stationary unit (FIG. 9) would be connected via itstelephone wire and male jack 198 directly to the public telephonenetwork. Therefore a PU-SU-CS link, free of any wireless segments, couldbe initially established. The advantage of this approach (as opposed tothe direct PU-CS link) is that the absence of any wireless segmentwithin the system will render the link robust. The disadvantage of thisapproach is that in order for the system to be usable in conjunctionwith a victim, another connection must be established when the PU istransported to the side of a victim; Either a wireless PU connection (toeither the SU or the CS) must be established; or a wire must be extendedfrom the PU (to either the SU or a female jack of the public telephonesystem).

In this PU-SU-CS format, the sequence of events could be:

a) button press;

b) the PU, over its connection to the SU via connectors 188 and 190,causes the SU to attempt to establish a connection with the CS;

c) the SU establishes a connection with the CS; the PU-CS link is thencomplete since PU is already connected to SU via connectors 188 and 190;the enabler and the MP can now communicate; and

d) the PU then attempts to establish a wireless connection with the SU.

The analysis of the backup approaches for the two-segment PU-SU-CS linkcan be dichotomized by considering: a) the situation in which thetwo-segment approach is initially successful (Section 4.1.2.4.2.1,below); and b) the situation in which the two-segment approach initiallyfails (Section 4.1.2.4.2.2, below). The backups ultimately consist ofthe same approaches as those discussed in Sections 4.1.2.4.1.1 and4.1.2.4.1.2 above, except that: a) the backups also include an attemptto establish a direct PU-CS link (This link assumed to have failed inthe backup approaches discussed in Sections 4.1.2.4.1.1 and4.1.2.4.1.2.); and b) the order in which the backups are selected maydiffer from that in the Sections hereinabove.

4.1.2.4.2.1 Two-Segment Default; Initial PU-CS Link Successful

Once step (c) is successfully completed, the exchange of vitalinformation between the enabler and the MP can begin (via the wireconnection between the PU and the SU), while the system attempts toestablish a wireless connection between the PU and the SU. If theattempt (step (d), above) is successful, a proper wireless PU-CS linkwill have been established, and the PU is ready for detachment from theSU, if the MP decides that the detachment is necessary (based on theenabler's description of the medical emergency).

If the attempt (step (d) above) is unsuccessful, the PU may then attemptto establish a wireless connection directly with the CS. If the latterattempt is successful, a proper wireless PU-CS link will have beenestablished. If the latter attempt is unsuccessful, the situation is theone described by State #3, Table 8; three backup options are listed inthe table and described in paragraphs (a), (b) and (c) in Section4.1.2.4.1.1. These options include extending the PU-SU wire connection(paragraphs (a) and (b), Section 4.1.2.4.1.1), moving the PU to thevictim and then attempting either a wire or wireless PU-CS connection(paragraph (c), Section 4.1.2.4.1.1) or using the AED/P function of thePU (paragraph (c), Section 4.1.2.4.1.1).

An alternate sequence is possible as the follow-up to step (c) (of thisSection). Instead of next performing step (d), in which the PU attemptsto establish a wireless link with the SU, the PU could instead attemptto establish a wireless link with the CS. If this failed, it could thenattempt to establish a wireless link with the SU; and if the latterattempt failed, the three backup options of paragraphs (a), (b) and (c)of Section 4.1.2.4.1.1 would be employed.

There a multiple possible variations in the timing of the setup of thewireless version of the PU-SU connection: a) the PU-SU connection couldbe wireless from the beginning, i.e. from the time of button press; b)the PU-SU connection could initially be via connectors 188 and 190, butattempts to establish a wireless PU-SU connection could proceed before,or at the same time as the attempt to establish the SU-CS connection(rather than first establishing the SU-CS connection, as is the scenariodescribed earlier in this Section). If, using one of these variations(in the timing of the setup of the PU-SU wireless connection), the PU-CSlink fails to be established, the backups are among those alreadydescribed including: a) attempting to use a wire connection for thePU-SU segment; b) attempting a direct PU-CS link; and c) using AED/Pbackup.

4.1.2.4.2.2 Two-Segment Default; Initial PU-CS Link Unsuccessful

According to the four step scenario described in Section 4.1.2.4.2,button press does not result in the establishment of a two segment PU-CSlink, then: a) the PU-SU wire connection (step (b)) will have failed;and/or b) the SU-CS connection (step (c)) will have failed.

A logical backup option would then be to try to establish a direct PU-CSlink. If this failed, an attempt to establish a wireless PU-SUconnection would follow. If both of these attempts failed, the backupwould be the AED/P function of the PU (paragraph (c), Section4.1.2.4.1.1).

Alternatively the order of the aforementioned wireless attempts could bereversed, such that the wireless PU-SU connection is first attempted,and if it fails, the wireless PU-CS connection is attempted. Again, theAED/P function is the backup if both of these fail.

Failure to establish either a PU-SU connection or a SU-CS connection ishighly unlikely for the reasons stated above at the conclusion ofSection 4.1.2.4.1.2

4.1.2.4.3 Redundant Links, in which There is Both a Direct PU-CS Linkand an Indirect PU-SU-CS Link

Another approach to the establishment of the PU-CS link is to attempt tosimultaneously establish both a direct PU-CS link and an indirect (twosegment) PU-SU-CS link. There could be up to three simultaneous initialattempts including: a) a direct PU-CS (wireless) link; b) an indirectPU-SU-CS link, in which the PU-SU segment is a wireless connection; andc) an indirect PU-SU-CS link in which the PU-SU segment is a wireconnection.

As soon as any one of these was established communications between theenabler and the MP could begin. There would then be multiple options:

a) If the first established link is a direct PU-CS link, a second linkmight or might not be attempted involving the PU-SU-CS route, with awireless PU-SU connection. If established, the second link could then beavailable as an immediate backup, if the PU-CS link is interrupted.

b) If the first established link is an indirect PU-SU-CS link, in whichthe PU-SU connection is wireless, a second link might or might not beattempted involving a direct PU-CS link. If established, the second,direct PU-CS link could then be available as an immediate backup, if theindirect PU-SU-CS link is interrupted.

c) If the first established link is an indirect PU-SU-CS link in whichthe PU-SU segment is a wire connection, a second route must beestablished (to allow detachment of the PU from the SU). Approaches inwhich only one second route is established (i.e. either a wireless PU-SUconnection or a wireless PU-CS connection) have been described above inSection 4.1.2.4.2.1. Another alternative is to attempt to establish bothwireless connections; one could then serve as the primary route and theother as a backup

If none of these three routes were viable, the backup would be via theAED/P function of the PU, described above in Section 4.1.2.4.1.2.

The advantage of establishing multiple simultaneous communication routesis that it renders the system more robust. The disadvantage is apotential cost increase.

Embodiments of the invention with a larger number of simultaneous routesbetween the PU and the CS are possible.

4.1.2.4.4 More Elaborate Routes for the PU-CS Link

Embodiments of the invention in which the routing for the PU-CS link isother than as described above (the direct link and the indirect PU-SU-CSlink) are possible. These include:

a) PU-SU-CS links which use a SU different than the SU to which the PUwas attached;

b) links in which two or more SUs operate in tandem (one of which may ormay not be the SU to which the PU was initially attached;

c) links in which there are two or more PUs operating in tandem (seeSection 4.5.7.5.2.2, below);

d) links in which there are two or more central stations operating intandem; and

e) combinations of (a) through (d), above.

4.1.2.4.5 Depth of Handshake Layers

Since the audio handshake (layer 3, Section 4.1.2.3.3) and theinformational handshake (layer 4, Section 4.1.2.3.4) between the enablerand the MP involve actual conversation, neither one can take place untilboth the PU-SU segment and the SU-CS segment have been established.Therefore, in the discussion in Sections 4.1.2.4.1 through 4.1.2.4.4, ithas been assumed that either a PU-SU segment or a SU-CS segment iscomplete as soon as the first two layers of handshake occur. The third(and then the fourth) layer handshakes (between the enabler and the MP)are attempted after: a) both the PU-SU and the SU-CS segments areestablished (with completed first and second layer handshakes); and/orb) the PU-CS link is established (with completed first and second layerhandshakes).

4.1.3 Phase Three: Transport of PU to Victim; Victim-MP Handshake; PUSetup at Victim's Side 4.1.3.1 PU Release and Transport

Referring again to Table 6, phase three begins when the MP decides thatthe PU should be used for a resuscitation effort, and, having sodecided, issues a command to release the lock which secures the PU tothe SU. Preferred embodiments of the invention have backup lock releasemechanisms which may be either mechanical, electrical or both (seeSection 2., description of FIGS. 8 and 9).

During the time that the enabler is transporting the PU to the victim'sside, there is frequent reassessment of the quality of the enabler-MPlink. If the link either deteriorates in quality or is lost as the PU isbeing moved, the MP, the system, and/or the enabler may utilize any ofthe backups listed in Table 7 or Table 8 and discussed in conjunctionwith these tables. If the MP notes that the quality of the enabler-MPlink is deteriorating as the PU is being moved, he may so inform theenabler and may provide specific corrective instructions to the enabler(see tables 7 and 8 and the associated discussion).

Phase three, like phase one, also includes an interval of variableduration, encompassing the transit time for the enabler carrying the PUto the victim's side. The enabler's speed, while carrying the PU, isassumed to be 1 mile per hour slower than it was when he was walkingwithout the PU, and hence a travel time that is 11 seconds longer thanthe phase one travel interval is allotted.

4.1.3.2 Handshakes Linking Victim and MP

After the electrode pad is applied during phase three, an electricallink between the victim and the MP, consisting of a layered sequence ofhandshakes, establishes: a) that the electrode pad is making appropriatecontact with the victim; and b) that the diagnosis is ventricularfibrillation.

4.1.3.2.1 The Four Layer Victim-MP Link

The victim-MP link is conceptually similar to the link between theenabler and the MP described above. Table 9, below, summarizes the mainfeatures of this series of handshakes.

TABLE 9 Four Layers of Handshake Linking Victim and MP Layer HandshakeBackup Backup Backup # Type Between #1 #2 #3 1 Communi- PU & CS Δ routeΔ mode MC = 2 cation 2 Data/ PU & CS Δ coding Δ HS MC = 2 Commands 3Electrical 3A MP to Vi VI & MP pressure Δ electrode Δ pad 3B Vi to MP VI& MP p/Δ gain Δ electrode Δ pad 4 Informa VI & MP Δ gain Δ ECG lead Δpad tionalThe handshakes which constitute layers 1 and 2 will have already beenestablished during the enabler-MP link, before phase three begins. Inaddition, the ongoing functionality of these two layers is continuouslyre-evaluated. In layer 3 of the victim-MP link, the handshake is basedon: a) the determination that impedance measurements in the circuitsthat include the pad electrodes and the victim are within the properrange (referred to in the table as “MP to victim”); and b) adequatequality of the electrical signals, if any, recorded from the victim(referred to in the table as “victim to MP”). Layer 4, the informationalhandshake, consists of the MP reading the electrocardiogram signals andthereby diagnosing the victim's heart rhythm.

As was the case with the link between enabler and MP: Within the linkbetween the victim and the MP, layer 2 is based on an intact layer 1,layer 3 is based on an intact layer 2, and layer 4 is based on an intactlayer 3.

4.1.3.2.2 Backup Systems for Failure in the Victim-MP Link

The backups for problems within the first two layers of the Victim-MPlink are similar to those for the enabler-MP link. The electrical (thirdlayer) handshake, analogous to the audio handshake of the enabler-MPlink, has backups intended to address a poor electrode-victim interface.

If impedance readings are high (third layer handshake; MP to victim),the MP may ask the enabler to temporarily press down over the section ofthe pad or pads which show a high impedance, hoping to thereby improveelectrode-victim contact. If this fails, the MP may be able to workaround the problem by using other better functioning electrodes, if theyare present in adequate number and location. If neither of these issuccessful, the MP may ask the enabler to remove the electrode pad, andto reapply it or another pad.

If the ECG signal is of poor quality (third layer handshake; victim toMP), the MP has all of the options previously mentioned for improvingthe impedance. The notation of p/Δ gain refers to dual first level MPoptions of either: a) asking the enabler to apply pressure over the pad,as described above; or b) changing the amplifier gain on the channel(s)corresponding to a low amplitude ECG signal.

During the informational phase, when the MP must diagnose the rhythmabnormality, the first level of backup involves switching the ECG lead.This is a non-mechanical process which involves looking at differentpairs of recording electrodes, hoping to identify a pair with a signalthat can lead to the rhythm diagnosis. Besides the backup options ofchanging gain and changing electrode pad, there are a variety of signalenhancing options that are discussed below in Section 4.3.1.2.

4.1.3.3 MP Commands, Confirmation Signals and Error Signals

Confirmation signals are first utilized in phase three, and extensivelyin phase four. Like the handshakes, they are an important feature of anemergency management system in which the expert who is making andenacting decisions (the MP) is physically separated from the device thathe is controlling. In a preferred embodiment, confirmation signals tellthe MP that the command that he initiated has reached a certaincheckpoint along its intended route. Error signals tell the MP that acommand failed to reach a certain checkpoint. Other types of errorsignals inform the MP of faults within the system, or faults at theperiphery of the system. System is defined as the hardware and softwarewhich comprise the PU or PUs, the CS, and the SU (if any). The peripheryof the system is defined as any device or individual (other than thevictim) which interfaces with the system. Such devices would includeblood pressure and oxygen saturation sensors, and the electrode pads.Faults involving individuals interfacing with the system includeimproper EMT or MP identification.

A simplified version of the sequence of events following an MP command,including confirmation signals, is

a) MP issues command;

b) CS transmits the command;

c) PU receives the command;

d) PU executes the command;

e) PU transmits a confirmation signal that indicates that the commandwas executed;

f) CS receives the transmitted confirmation signal;

g) CS displays the confirmation signal; and

h) MP sees the confirmation signal.

In the aforementioned format, there is a single confirmation signal foreach command which indicates its successful execution. In a preferredembodiment of the invention, a more complex system of confirmationsignals is used which utilizes multiple confirmation signals for eachcommand. For a given command, each successive confirmation signalconfirms the proper progress of the command as it passes each of anumber of checkpoints in its traversal of the route from MP to point ofexecution. Command confirmation may occur:

a) after the command is encoded, indicating that it was properlyformulated and encoded;

b) after the command is transmitted, indicating that transmission wasproper;

c) after it is received by the PU; and

d) after it is executed by the PU.

Error signals are made available to the MP to indicate failure of thecommand to traverse a given point in the system.

Identification of the location of a fault in the system is based onwhich particular confirmation signal(s) and which particular errorsignal(s) are received by the MP. Embodiments in which a greater or alesser number of confirmation and error signals occur are possible.

In the event of failure of execution of a command, the MP can exercisevarious backup options including:

a) repeating the command;

b) reassessing the robustness of communication and performing necessaryremedial measures (see below);

c) handing control over to the built in backup system, the AED/P; or

d) the substitution of a redundant hardware unit for a failed one (byelectronic means), once the failure has been located.

This confirmation system will be described in detail below.

4.1.3.4 Telemetry Signals

Telemetry signals may be considered to be analogous to confirmationsignals. Telemetry signals are sent from PU to CS, indicating a PU-basedevent that was not initiated directly by the MP. Examples includedetachment of the PU from the SU by the enabler, and touchdown of the PUafter proper orientation by the enabler. Other telemetry signals mayindicate faults within the system, or be part of a periodic systemdiagnostic evaluation.

4.1.4 Phase Four: Emergency Medical Management of the Cardiac Arrest bythe Medical Professional

The fourth of six phases of the hypothetical cardiac arrest encompassesthe treatment, by the MP, of the victim's heart rhythm abnormalities.For illustrative purposes, four treatment steps are shown. In its mostsimplified form, a cardiac arrest could consist only of one step: asingle corrective shock, followed by the emergence of a normal rhythm.In order to more fully illustrate some of the capabilities of apreferred embodiment of the invention, the arrest described herein (inconnection with Tables 6 and 10) is a more complex one.

4.1.4.1 Defibrillation and Pacing by the MP

In the arrest described in Tables 6 and 10, the first shock fails toterminate VF. The MP then alters the shock vector by changing one of thepair of electrode pads through which the defibrillating pulse isapplied. The MP then causes the PU to deliver a second shock. The MPnotes that the second shock was successful in terminating VF, but thatasystole (the absence of any cardiac electrical activity), has ensuedpost-shock. He treats this by causing the PU to deliver pacing stimulito the victim's chest, at a rate of 60 beats per minute.

4.1.4.2 Other Actions Directed by the MP to Support Blood Pressure

Two minutes and forty three seconds into this hypothetical arrest, anacceptable heart rhythm has been restored. The MP must now determine ifthe restoration of reasonable electrical function to the victim's heartis accompanied by a parallel restoration of mechanical function. The MPmust therefore determine if the victim has adequate blood pressure andrespiratory function. In order to make this determination, the enableris brought into play again, briefly. The MP asks the enabler to assistin the application of a non-invasive blood pressure device and atransducer for measuring the victim's blood oxygen status. The MPobserves a borderline low blood pressure. He then reduces the pacingrate and observes the emergence of a normal rhythm, and a rise in bloodpressure. This completes phase four.

4.1.5 Phase Five: Management Immediately Post Electrical Resuscitation

During phase five, cardiopulmonary resuscitation is performed, if deemednecessary by the medical professional. The MP obtains victimidentification and prior medical information. The MP also communicateswith the en-route emergency medical team, and reports their estimatedtime of arrival to the enabler.

4.1.6 Phase Six: EMT Arrival, Transfer of Control of the PU from MP toEMT

The onset of phase six is marked by the arrival of the EMT. The MP may,if the EMT is appropriately qualified and identified, hand over controlof the PU to the emergency medical team. In the scenario described bythe sample arrest in Section 4.2, below, we assume that the EMT isdesirous of such transfer.

4.1.6.1 EMT Choices Other Than Assuming Control of the PU CurrentlyAttached to the Victim

Other EMT choices include:

a) EMT wishes to assume control over rhythm management using anotherportable unit (hereinafter referred to as “new PU”) which is anembodiment of the invention, but not the same unit which up until thatmoment was used on the victim (hereinafter referred to as “old PU”) (Thenew PU and the old PU may or may not be identical embodiments of theinvention.).

b) EMT wishes to have the MP continue to manage heart rhythmabnormalities, using the old PU, with EMT function then restricted to(i) starting an intravenous line for the victim, (ii) giving intravenousmedication if necessary, (iii) performing CPR (cardiopulmonaryresuscitation) if necessary and (iv) transporting the victim to thehospital;

c) the same scenario as (b), except that EMT wishes to do this with thenew PU;

d) EMT wishes to assume control over rhythm management using adefibrillator apparatus which is different than the invention;

4.1.6.2 Handshakes Linking EMT and MP

The transfer of control of the PU from MP to EMT is based on a series offour handshakes, which are conceptually similar to the four handshakeswhich establish the enabler-MP link at the start of the emergency.Layers 1 and 2 of the EMT-MP link may be identical to those of the EN-MPlink: communication and data/command handshakes, running continuously inthe background. Layer 3 is an audio handshake between the MP and theEMT. They both confirm that they can adequately hear each other, withthe MP making any appropriate adjustments to facilitate this, as was thecase with the enabler-MP handshake. The fourth handshake involves theexchange of information between the MP and the EMT. After the audio linkis secure, the MP asks the EMT for either a password (“PWD”) (which maybe numeric or one or more words), or seeks other evidence that EMT isrepresented by an appropriate, competent individual (which may bedetermined by fingerprint, voice, facial and/or iris recognition, or bydirect conversation). EMT identification thus constitutes theinformational, fourth layer of the EMT-MP link.

The four layers which constitute the link between the EMT and the MP,and the backups for these four layers are summarized below, in Table 10:

TABLE 10 Four Layers of Handshake Linking EMT and MP Layer HandshakeBackup Backup Backup # Type Between #1 #2 #3 1 Communi- PU & CS Δ routeΔ mode PWD: cation MC = 3 2 Data/ PU & CS Δ coding Δ HS PWD: Commands MC= 3 3 Audio 3A MP to EMT MP & EMT Headset Voice Pr Text Pr 3B EMT to MPEMT & MP Headset Keyboard SpeechRec 4 Informa- EMT & MP Interp'r VoiceRe Video CAM tional

4.1.6.2.1 First and Second Layers of EMT-MP HS: Password Which GivesControl of PU to EMT, Rather Than to Giving Control of PU to AED/P

As discussed in Section 4.1.3.2.1, the handshakes which constitutelayers 1 and 2 will have already been established during the enabler-MPlink, and the ongoing functionality of these two layers is continuouslyre-evaluated. As is indicated in Table 10, the first two levels ofbackup for an EMT-MP handshake failure in layer #1 or #2 are identicalto those for the enabler-MP link.

The third level of backup for an EMT-MP handshake failure in layer #1 or#2 differs from that of the enabler-MP handshake. It involves the use ofa password by the EMT. The password, when appropriately supplied, causesthe PU to enter Master Control State 3, which enables control of theunit by the EMT. This approach differs from that used in the enabler-MPlink, in which the third level of backup for handshake failure in layers#1 and #2 is entry of the PU into Master Control State 2, enablingcontrol of the unit by the AED/P. The rationale for this difference inapproach is that if communication (or data/commands exchange) betweenthe PU and the CS fails when the EMT is present, it makes more sense togive control of the PU over to the EMT, rather than giving it over tothe AED/P. Accordingly, the EMT is provided with a password which, inthe event of failure of PU-CS handshakes at layers #1 or #2, will allowthe EMT to cause PU to enter Master Control State 3, giving EMT controlof the PU. The password may be supplied to the EMT when the EMT issummoned, or at an earlier time. Alternatively, password acceptance mayrequire matching pre-programmed EMT anatomic features (fingerprint,iris, etc.).

In a preferred embodiment, as long the handshakes in layers #1 and #2are intact, password acceptance requires the participation of the MP,and occurs in level four. Only in the event of handshake failure inlayers #1 or #2, would the EMT password cause the transfer of control ofthe PU to the EMT, without the MP causing such transfer. This approachmakes the system least likely to have its control usurped by aninappropriate person.

4.1.6.2.2 Third and Fourth Layers of EMT-MP HS

The third layer of this handshake, is entirely analogous to the thirdlayer of the enabler-MP handshake. The goal is the establishment andconfirmation of adequate quality audio in both directions. The backupsfor the third layer are the same in both cases.

As indicated above, the informational handshake of level four is thepassword. Backup systems are intended to enhance EMT identification, inthe event that a putative password does not match. The backups includean interpreter, and techniques for recognizing individualcharacteristics including voice (Voice Re), facial and other anatomicfeatures (via video camera).

4.1.7 Management by the EMT, after Transfer of PU Control to the EMT, bythe MP

The traditional role of the emergency medical team includes all aspectsof the management of the victim from the time they arrive at the sceneof the emergency, until they arrive in hospital.

4.1.7.1 Transfer of PU Control

Once the EMT is deemed by the MP to be appropriate, and desirous ofassuming control over the PU, the MP may transfer control of the PU tothe EMT. Phase seven begins when the MP decides that control of the PUshould be transferred to the EMT, and, having so decided, issues acommand to effect such transfer. Phase seven ends when both: a) thevictim is no longer attached to the PU; and b) when the PU has beenreturned to the SU (see Section 4.5.7.8).

4.1.7.2 Briefing of EMT by MP

Following the transfer of control, the MP provides the EMT withinformation which summarizes the events which occurred prior to thearrival of the EMT, and other data deemed to be important by either theMP or the EMT. Such information would include:

a) the victim's current status including (i) his rhythm status over thelast few minutes (Meanwhile, the victim's real time rhythm status, i.e.the current ECG, would be displayed on one of the PU screens.) and (ii)his current vital signs;

b) the victim's initial heart rhythm;

c) the major events that took place during the resuscitation, i.e.defibrillation and pacing, and the results of each therapeuticintervention by the MP;

d) the victim's blood pressure recordings during the event;

e) the victim's respiratory status during the event;

f) the elapsed time since MP involvement with the emergency began;

g) the elapsed time since the emergency began (if known);

h) the victim's latest and prior states of responsiveness;

i) information obtained from enabler's initial description of thevictim, i.e. that obtained immediately before MP release of the PU tothe enabler;

j) information about the victim's medical history; including (i) eventsimmediately preceding the current emergency and (ii) events and medicalconditions which predate the current situation; and

k) information about the victim's medications, if any;

l) information about the victim's medication allergies, if any;

m) information about victim's next of kin, if known. Items (a) through(f) are stored within the PU memory for the duration of the event. Theyare also stored within the CS memory, as are items (j) through (m), ifknown. Items (g), (h) and (i) may be related to the EMT by the MP. Allvictim and event data, audio and video recordings become a part of thepermanent CS record.

Storage and transmission of victim-related and event-related informationis performed in compliance with all local and federal statutes regardingprivacy, encryption and restriction of access.

The duration of the information presentation and the level of detailwill depend on: a) the severity of victim's condition at the moment ofEMT take-over; and b) the number of EMT personnel. (A larger team meansthat someone is more likely to be free to obtain the information.)

The information may be presented in any of the following formats:

a) enabler narrative by voice communication;

b) text summary, on one of the PU screens;

c) ECG summary (the important recordings made during the resuscitationprocedure), on one of the PU screens;

d) text printout (A small printer may be included in the PU.);

e) ECG printout; and

f) combinations of (a) through (e).

In addition to supplying the EMT with patient related information, theMP may, if necessary, provide the EMT with information about the use andoperation of the PU.

4.1.7.3 Method of PU Operation by the EMT

The EMT uses the PU in a similar fashion to the way that the medicalprofessional uses his console at the central station. That is, the PUscreens 156: a) display vital information such as the victim's ECG,blood pressure and respiratory status; b) serve as touch sensitivescreens with the same screens for defibrillator and pacer control, andfor ECG viewing and electrode pad setup as those used by the MP (FIGS.29 through 40); and c) can display an appropriately truncated version ofthe Screen Menu (FIG. 43) used in the central station (The truncatedScreen Menu does not give the EMT access to screens which would beinappropriate and unnecessary for the EMT, such as the Video ControlScreen (FIG. 28). Additional screen capacity may be achieved withscreen-in-screen and split screen methodology, as was discussed inSection 2. In a preferred embodiment of the system, the PU may generateinstructional prompts, either voice or text, to help guide the EMTregarding PU operation.

4.1.7.4 MP Role During EMT Use of the PU 4.1.7.4.1 Medical and TechnicalSupport by the MP

In a preferred embodiment of the invention, the MP link with the PUremains intact, even after handoff of PU control to the EMT. Thereforethe MP may continue to:

a) view victim data (ECG and other);

b) view EMT commands;

c) speak with the EMT; and

d) observe the arrest scene.

Therefore, there are a number of possible formats for the relationshipof MP to EMT, during EMT use of the PU. These include:

a) active involvement by the MP, in an advisory capacity, in medicaldecision making (i.e. MP makes suggestions about victim managementwhenever MP feels it is appropriate);

b) involvement in a medical advisory capacity, only when consulted bythe EMT;

c) active involvement by the MP, in an advisory capacity, in a technicalsupport role (i.e. advising the EMT about PU operation whenever MP feelsit is appropriate);

d) involvement in a technical support role, only when consulted by theMP; and

e) no MP involvement whatsoever.

“Active” may refer to any frequency of giving advice, from frequent toinfrequent. Which of (a) through (e) is selected may be based on bothEMT and MP preference, and may be based on local statutes or protocol.The choice of (a) through (e) may vary during the course of a particularemergency. For example: Although the EMT might be fully capable ofmedical management of the victim and proper use of the PU, he might failto notice a sudden change in the victim's heart rhythm. This could occurwhile the EMT is starting an intravenous line for the victim. The MP, insuch a situation, could immediately inform the EMT.

Medical advice which the MP could provide includes:

a) helping the EMT make a correct rhythm diagnosis;

b) helping the EMT select the correct treatment modality (e.g. shockversus giving intravenous medication);

c) helping the EMT select the correct treatment parameters (e.g. highenergy shock versus low energy shock);

d) advising the EMT as to the adequacy of CPR performance (e.g. bymonitoring oxygen saturation);

e) advising the EMT of a sudden change in the victim's status which theEMT may not have noticed (see example above); and

f) pharmacologic advice (see below).

At any time, the EMT may request that the MP resume control of the PU.This may occur if:

a) additional electrical therapy is necessary (defibrillation or pacing)and the EMT feels that the MP's medical expertise is superior to EMT's

b) the EMT feels that the MP's technical expertise (regarding operationof the portable unit) is superior to EMT's;

c) one or more members of the emergency medical team is involved inmedical activities such as CPR or intravenous line placement, which donot allow them to pay adequate attention to heart rhythm issues;

d) one or more members of the emergency medical team is involved intransport activities, which do not allow them to pay adequate attentionto heart rhythm issues;

e) combinations of (a) through (d).

4.1.7.4.2 Pharmacologic Support by the MP

Once one of the members of the emergency medical team has started anintravenous line for the victim, there is the opportunity to administera variety of intravenous medications including:

a) drugs to help regulate the heart rhythm (antiarrhythmic drugs);

b) drugs to increase the intensity of the heart's mechanical action(inotropic drugs);

c) drugs which increase the heart rate (chronotropic drugs);

d) drugs which alter the metabolic status; and

e) drugs which prevent blood clotting (antithrombotic agents) or promoteclot dissolution (thrombolytic agents).

The EMT opportunity to administer intravenous medication adds anotheritem to the potential MP advisory role. The MP advice may be based on:a) the MP's own expertise; b) rapid access to other experts inpharmacologic matters; and c) rapid access to databases which containpharmacologic information. The MP pharmacologic advice to the EMT mayinclude:

a) suggestions or information about choice of drug (if any), and dosage;

b) suggestions about rate and route of drug administration;

c) advice about expected drug effect;

d) advice about potential drug-drug interactions;

e) reminders about current victim medications (if known) drug allergies(if known).

4.1.8 MP Role After Victim Arrives at the Hospital

The MP may continue to function in an advisory capacity after the victimreaches a hospital. That is, treating physicians at the hospital whichreceives the victim may wish to utilize the MP, because of a number ofpotential of advantages to such an approach including:

a) the MP's high degree of expertise and experience in the management ofheart rhythm abnormalities may exceed that of any of the physicians inthe hospital;

b) the MP's rapid access to other experts;

c) the MP's rapid access to pharmacologic databases;

d) the MP's rapid access to the victim's past medical history; and

e) the fact that the MP has become familiar with the victim and hisresponse to therapy over the course of the current medical event.

It is furthermore possible that hospital physicians may request that theMP resume control of electrical therapy, for each of the reasons (listedabove) that EMT may make such a request.

4.2 Sample Cardiac Arrest: Correspondence Between Events During theArrest, Flow Diagrams, Screens, Handshakes and Confirmation Signals

Table 11 shows the sequence of events that constitute the hypotheticalcardiac arrest. This table also shows the correspondence between:

a) events during the arrest;

b) flow diagrams, FIGS. 12 through 23, showing the functionalinteraction among the system, the enabler and the medical professional;

c) some of the actual screens that the MP views during an arrest (Thecomplete set of screens consists of FIGS. 24-44. Ten of the 19 screensare mentioned in Table 11.);

d) the handshakes, discussed above and summarized in Tables 7, 8 and 9;and

e) the confirmation signals which let the MP know that his commands wereproperly executed.

Explanatory comments in the table are indented.

TABLE 11 Events During an Hypothetical Cardiac Arrest Flow CS TimeDiagram Console m:ss Event FIG. # FIG. # Phase One 0:00 Enabler (EN)sees emergency victim (VI) and decides to help 0:01 EN heads for nearestPortable Unit (PU) 0:31 Button press by EN 12 Phase Two 0:31 PUtransmits handshake (HS) signals 12 25 to Central Station (CS) 0:32Completion of Communication HS 12 25 between PU and CS 13 (Table 7,VI-MP Link, HS #1) 0:32 Completion of Data/Command HS between 14 25 PUand CS (Table 7, HS #2) 0:32 CS identifies PU as Unit #643025, locatedin Columbus, Ohio 0:33 MP identifies himself 15 0:37 EN confirms that hecan hear the MP; 15 25 MP confirms that he can hear the EN; Theseconstitute completion of Audio HS between EN and MP (Table 7, HS #3A and#3B) 0:41 MP asks EN to describe the emergency 16A 0:44 Begin EN'sdescription of the 16A emergency 0:50 End EN description; 16A MP decidesthat this emergency warrants intervention by MP and PU This constitutescompletion of Informational HS between EN and MP (Table 7, HS #4) PhaseThree 0:50 MP issues commands to 16A 27 a) release PU lock b) call 9-1-1nearest to EN 0:50 CS transmits and PU receives 16A 44 Lock ReleaseCommand 24 0:51 Electromagnetic Lock releases PU from 16B StationaryUnit (SU) 0:51 PU transmits and CS receives lock 16B 44 releaseconfirmation 24 0:52 MP sees lock release confirmation 27 0:53 MP tellsEN to detach PU from SU, 16C 27 and to transport PU to VI 0:55 ENdetaches PU from SU; 0:55 PU transmits and CS receives and 24 44displays PU removal telemetry signal 0:56 MP sees removal telemetrysignal 16C 27 0:56 EN transports PU to VI; 17 During transport, MPprovides EN with additional instructions 0:56 During transport, there iscontinuous 25 updating of the link between EN and MP 1:37 EN tells MPthat he has arrived at 18A VI's side 1:39 MP tells EN how and where toput PU 18A down 1:41 EN puts down PU; This automatically 18A 44 releasestool-kit door and transmits 24 PU touchdown telemetry signal; CSreceives and displays telemetry 1:42 MP sees PU touchdown telemetrysignal; 18A 27 On PU Deployment Screen, MP presses 28 GO TO VIDEOCONTROL SCREEN; This Brings up Video Control Screen 1:42 MP optimizesaudio to and from EN 18B 44 1:46 MP asks EN if VI is unconscious; 18D VIanswers affirmatively 1:48 MP, working from Video Control Screen, 18A 28extends video boom, so its end protrudes from PU 1:50 MP instructs EN inexposing VI's 18E 28 chest 2:00 MP determines that pad 204B is 18E 28optimal (5 large/7 small electrodes) and tells EN to get it from topshelf of tool-kit 2:05 EN pulls pad 204B, and the cable and 18E 28Universal Connector which attach pad to the PU, from the tool-kit shelf2:07 MP instructs EN in proper pad 18E 28 location, orientation, andapplication method 2:09 EN peels off pad cover; Cover removal 24 44telemetry signal is transmitted by PU and is received and displayed byCS 2:11 EN applies pad to VI's chest 2:14 MP sees that pad is properlyplaced; 18F 28 On Video Control Screen, MP presses 29 INITIAL ECGSCREEN; This brings up Initial ECG Screen 2:15 MP observes adequateimpedance value 18F 29 for each pad electrode This constitutes Part A ofthe Electrical HS between VI and MP (Table 9, VI-MP Link, HS #3A) 2:17MP notes that ECG is of good quality 18F 29 on Initial ECG Screen Thisconstitutes part B of the Electrical HS between VI and MP (Table 9, HS#3B) 2:17 MP diagnoses ventricular fibrillation 19 29 This constitutesthe informational HS between VI and MP (Table 9, HS #4) Phase Four 2:18MP selects MAIN DEFIB SCREEN on 29 Initial ECG Screen; This brings up 33Main Defib Screen 2:18 MP tells EN to avoid contact with VI 20 due toimpending defibrillator shock 2:19 MP decides to use defaultdefibrillation parameters (i.e. α and δ pads) 2:20 MP selects ALLDEFAULT VALUES, then 20 33 selects ACCEPT on Main Defib Screen 2:20 CStransmits and PU receives command 24 44 to begin charging PUdefibrillator capacitors; charging begins 2:23 Capacitor chargingcomplete; PU sends 24 44 and CS receives and displays charge completionconfirmation 2:25 MP notes charge completion signal, 20 24 confirmspersistence of VF, and ECG issues command to deliver shock by 33selecting DELIVER on Main Defib Screen 2:25 CS transmits shock commandto PU; 24 44 PU receives command and delivers default shock to VI 2:25PU sends, and CS receives and 24 44 displays shock confirmation data2:26 MP notes confirmation and notes 19 24 persistence of VF, post-shockECG 2:27 MP decides to deliver another 20 defibrillating shock 2:28 MPtells EN to avoid contact with VI 20 due to impending defibrillatorshock 2:29 MP decides to alter defibrillation 20 vector (by using the αand ε pads) to enhance chance of success of next shock) 2:30 MP selectsOTHER under ELECTRODES 20 33 on Main Defib Screen; This brings up 31Five Electrode Setup Screen 2:31 MP selects α, ε electrode pair on Five20 31 Electrode Pad Setup Screen by 33 touching the followingsequence: 1) α 2) ε 3) ACCEPT This brings up Main Defib Screen 2:33 OnMain Defib Screen, MP selects 20 33 additional parameters of upcomingsecond defibrillator shock by touching the following sequence: 1) MAXunder ENERGY 2) NO under SYNCH 3) DEFAULT under WAVEFORM 4) ACCEPT 2:35CS transmits and PU receives commands 24 44 to switch to α, ε pair ofdefibrillator electrodes and to begin charging PU defibrillatorcapacitors; charging begins 2:38 Capacitor charging complete; PU sends24 44 and CS receives and displays charge completion confirmation 2:40MP notes charge completion signal, 20 24 confirms persistence of VF, andECG issues command to deliver shock by 33 selecting DELIVER on MainDefib Screen 2:40 CS transmits shock command to PU; 24 44 PU receivescommand and delivers second shock to VI, via α and ε pads 2:40 PU sends,and CS receives and 24 44 displays shock confirmation data 2:43 MPobserves termination of VF and 19 ECG notes presence of asystole (flatline); MP decides to begin pacing the heart, to accelerate the heartrate 2:44 MP selects MAIN PACING SCREEN on 23 33 Main Defib Screen; Thisbrings up 38 Main Pacing Screen 2:46 MP selects ALL DEFAULT VALUES; then23 38 selects DELIVER on Main Pacing Screen 2:46 CS transmits command toPU to begin 24 44 pacing at 60 BPM (pacing mode, pulse width, amplitudeand pad choice are also specified in the command) 2:46 PU receivescommands and begins 24 44 pacing at 60 BPM 2:46 PU sends, and CSreceives and 24 44 displays pacing confirmation data 2:48 MP notespacing at 60 BPM ECG 2:48 MP instructs EN to remove blood 22 pressurecuff and oximetry sensor from tool-kit and apply them to VI 2:49 FromScreen Menu, MP selects VIDEO 44 CONTROL SCREEN; This brings up 28 VideoControl Screen from which MP Displays instructional video for EN 2:56 MPobserves that victim's blood pressure BP is 80/50 (low) and that theoxygen SAT saturation value is 96% (adequate) 2:57 MP decides to reducepacing rate in order to: a) observe victim's underlying rhythm; and b)in attempt to increase victim's blood pressure by restoringatrioventricular synchrony 2:57 MP selects OTHER next to RATE on 23 38Main Pacing Screen; 40 This brings up Bradycardia Pacing Rate Screen2:58 MP touches 55, followed by ACCEPT 23 40 on Bradycardia Pacing RateScreen; 38 This returns Main Pacing Screen 2:59 MP sets default valuesfor other 23 38 pacing parameters by touching: 1) DEFAULT underAMPLTIUDE 2) DEFAULT under WAVEFORM 3) DEFAULT under PACING ELECTRODES4) DEFAULT under SENSING 5) DELIVER 3:01 CS sends command to PU tochange 24 44 pacing rate from 60 to 55 BPM 3:01 PU receives command andchanges 24 44 pacing rate to 55 BPM 3:01 PU sends, and CS receives and24 44 displays pacing confirmation data 3:04 MP observes emergence ofvictim's own 19 ECG normal sinus rhythm at 58 BPM 3:05 MP decides thatpacing is no longer 38 necessary and touches STOP PACING on Main PacingScreen 3:05 CS sends command to PU to stop pacing 24 44 3:05 PU receivescommand and stops pacing 24 44 3:05 PU sends, and CS receives and 24 44displays stop pacing confirmation 3:07 MP observes that pacing hasceased ECG 3:18 MP observes that victim's blood BP pressure has risen to100/60 The victim's heart rate, rhythm blood pressure are now consideredto be adequate. Phase Five 3:18 MP asks EN to obtain VI's name and otheridentifying data, from persons accompanying the VI, from the VI himself,or from VI's wallet 3:24 EN provides MP with VI identification 3:27 MPenters VI identification into Archival Database 3:31 MP views display ofVI past medical history, obtained from databases 3:36 MP informs EN thatestimated time of 27 arrival of local Emergency Medical Team (EMT) is infour minutes Phase Six 7:25 Arrival of EMT 7:27 MP identifies himself toEMT 7:31 EMT says that they can hear the MP; MP confirms that he canhear the EMT; These constitute completion of Audio HS between EMT and MP(Table 10, HS #3A and #3B) 7:35 MP asks EMT for password; EMT'sknowledge of password proves they are qualified to take over managementof the case from the MP 7:39 EMT provides password 7:43 MP confirms thatpassword is correct, i.e. it indicates a qualified EMT; MP decides totransfer control of PU To EMT This constitutes completion ofInformational HS between EMT and MP (Table 10, HS #4) Phase Seven 7:43MP informs EMT that password has been confirmed and that control of thePU will now be transferred to the EMT 7:47 On the Communications Statusand 25 Triage Screen, MP selects GO TO EMT 7:47 CS transmits command tochange the 24 44 Master Control Unit state from its present value of 1(MP control of the PU) to 3 (allowing EMT control of the PU); PUreceives command (Table 1) 7:47 Master Control Unit 130 changes 24 44state, allowing EMT control of PU; PU sends, and CS receives anddisplays change of state confirmation The transfer of control of the PUfrom MP to EMT is now complete; EMT can now control PU, using the samescreens that MP was using 7:48 MP briefs EMT about current victimstatus, about events that have transpired during the past eight minutes,and about victim's medical history and identification, if known Beyondthis point, the MP role and time allocations are highly variable and arediscussed in Sections 4.17, 4.18, 4.45, and 4.57. Phase seven ends whenboth: a) the PU is disconnected from the victim; and b) the PU isreturned to the SU.

4.3 Role of the Medical Professional 4.3.1 Expert Decisions Made by theMP During the Cardiac Arrest

One very important role of the MP is the making of expert managementdecisions. The expertise and judgment of the MP and the flexibility andcapability of the system allow the resuscitation procedure to beperformed as if a medical doctor specializing in heart rhythm disorders,or a highly trained emergency medical technician was actually present atthe emergency scene. Three examples of major MP decisions, which occurduring the sample arrest, are: a) the MP decision to change thedefibrillation vector for the second shock, and the capability of thesystem and the electrode pad to accommodate the decision; b) the MPability to reliably distinguish asystole from VF post second shock andhis decision to begin bradycardia pacing at that time; and c) the MPdecision to slow the pacing rate from 60 to 55, in an attempt to improvethe blood pressure by restoring AV synchrony. These three examples willnow be discussed, to be followed by a discussion of other significant MPmanagement decisions.

4.3.1.1 The MP Decision to Change the Defibrillation Vector for theSecond Shock

Our present understanding of the physiology of defibrillation is thatthe high voltage discharge depolarizes a significant fraction of thecardiac tissue. The shock thus momentarily prevents the propagation ofthe multiple fibrillatory wavefronts that are the basis of VF, andthereby causes the termination of VF. Since VF is a metastable heartrhythm, momentarily interrupting it allows for the emergence of agenerally more stable rhythm, the heart's normal (or sinus) rhythm.

However, if the electrode pads are located in positions that do notallow the shock to depolarize enough of the fibrillating heart muscle,the shock is ineffective and VF persists despite the shock. It istherefore common procedure, during the conduct of an actual VFresuscitation, for the physician or other properly trained person toselect alternate electrode pad positioning, if one or more shocks fail.Such repositioning is most likely to be necessary in the case of eithera large victim, or in certain medical disease states where the heartitself has enlarged considerably. In the preferred embodiments whichutilize multi-electrode pads, the MP can accomplish electroderepositioning electronically. In the case of the five electrode pad,shown in FIGS. 5A-E, the MP accomplishes the desired repositioning bysimply selecting the more laterally located ε electrode, in place of thepreviously ineffective δ electrode. The fact that the α,ε pair ofelectrodes encompasses a greater amount of cardiac tissue than thestandard α,δ pair makes it more likely to be effective.

The MP has a variety of options to choose from in the event of anineffective shock for VF. They include:

a) simply repeating the shock without changing any parameters;

b) changing the shock vector, i.e. changing the anatomic relationshipbetween electric current flow and the heart's position, as was done forthe second shock in the example discussed;

c) increasing the energy of the shock;

d) changing the waveform of the shock, and

e) instructing the enabler in the performance of CPR, and then shockingthe victim.

State of the Art AED systems do not have the flexibility to accomplishthe five options listed above. Furthermore, if they did have one or moreof these options, they would not be endowed with the superior ability ofa highly trained professional to choose which among the options would beideal. However, utilizing a preferred embodiment of this invention, amedical professional would have all of these options and be in aposition to choose intelligently from among them. Based on his judgment,the MP might be more inclined to choose the second option, i.e. a shiftin electrode location, if he:

a) noted that a previous shock using standard electrode positioning wasineffective;

b) knew from video observation (or enabler description) that the victimwas large;

c) knew from video observation that the multi-electrode pad had not beenpositioned perfectly at the time that the enabler placed it on thevictim's chest; and/or

d) knew, from either accessing the database or from a personaccompanying the victim, that the victim's medical history included anenlarged heart or a medical condition or diagnosis associated with anenlarged heart. (In the scenario in Table 11, the database is notaccessed until after the resuscitation is complete, but it could havebeen accessed earlier.)

4.3.1.2 MP Distinction Between Asystole and Ventricular Fibrillation

The second example of the combination of MP expertise and judgment andthe invention's flexibility and capability resulting in a successfuloutcome, relates to the MP diagnosis of asystole following the secondshock. Asystole, the absence of any cardiac electrical activity canoccur after a successful defibrillation shock. It is more likely tooccur after a long duration of VF, than after a brief episode. At times,the electrocardiographic distinction between VF and asystole is subtle.Although the “textbook” electrocardiogram (ECG) of VF consists of acontinuously varying high frequency, low amplitude oscillation, and the“textbook ECG of asystole is a perfectly flat, featureless line, attimes one sees ECG tracings which might be described as fallingin-between the aforementioned textbook descriptions. For example, duringthe phenomenon known as “fine VF,” the ECG undulations are so low inamplitude that the tracing may be misread as asystole. And during someepisodes that actually are asystole, the baseline may wander enough(either due to jostling of the victim, the pad or the cable, by theresuscitation team) so that even an expert cardiologist is uncertainabout whether to read the ECG as asystole or fine VF.

The diagnostic problem is compounded by the fact that the treatment forVF is entirely different than the treatment for asystole. Fine VF istreated by administering a defibrillator shock. Asystole is treated bypacing the heart. A defibrillator shock is useless for asystole andpacing the heart is impossible during VF. Thus the distinction betweenthe two rhythms is of much more than academic interest.

In principle, an algorithm could be created which could distinguishbetween these two rhythms as well as an expert professional. The realityis, that as of the current time, no algorithm with the discriminatingpower of the most expert professional exists.

If the distinction between these two rhythms is especially difficult,the options available to the MP using a preferred embodiment of thecurrent invention include one or more of the following:

a) recording for a longer period of time, in order to have a largerinformation sample;

b) asking enabler to make sure that no individual is, for the moment incontact with the victim or the cable between the victim and the PU;

c) causing the PU to sample the ECG more frequently than it does withnominal settings, resulting in more accurate ECG reproduction (In apreferred embodiment the system, according to the invention, allinformation is transmitted between the central station and the portableunit in digital form.);

d) digitizing the ECG signal with a greater number of bits per sample,resulting in more accurate ECG reproduction;

e) increasing the bandwidth allocated for transmission of ECGinformation, either (i) on the already established communication channelbetween the PU and the CS, or (ii) by establishing an additionalchannel;

f) switching ECG transmission temporarily to a non-real time format inwhich: (i) the amount of ECG information recorded per unit time isincreased (by increasing either the sampling rate or the number of bitsper sample), (ii) the information is temporarily stored in a buffer, and(iii) the information is transmitted over the nominal bandwidthallocation;

g) encoding the ECG information differently, using a real time format;

h) setting up another communication channel between PU and CS andtransmitting an analog version of the ECG signal i) in the event of adegraded ECG signal due to distortion due to communication problems,comparing the MP rhythm analysis with that of the on-site AED/P logicunit, 128;

j) making the decision to empirically shock the victim, i.e. making theassumption that the rhythm is fine VF; and

k) making the decision to empirically pace the victim, i.e. making theassumption that the rhythm is asystole.

Options (c), and (d) involve recording a reproduction of the ECG signal.Option (a) also provides more (but not more accurate) information forthe MP. Options (f), (g) and (h) involve changes in the format for ECGencoding. Option (i) would be useful if the MP still had diagnosticuncertainty, despite any of the options (a) through (h) directed atproviding the MP with more or higher quality ECG information.

In the scenario described in Table 11, the MP was able to make thedistinction, correctly diagnosing asystole at 2:43 and institutingcardiac pacing as of 2:46.

4.3.1.3 MP Effort to Improve Blood Pressure

The third example of MP expertise and judgment combining favorably withthe invention special features involves the MP commands at 2:57 toreduce the pacing rate. Proper management by the MP, in this scenario,involved giving consideration to the possibility that the low bloodpressure (80/50) during pacing may have been caused or accentuated bythe pacing itself. This phenomenon is not uncommon and is sometimesreferred to as pacemaker syndrome. This syndrome may occur when pacingthe heart results in an unnatural sequence of electrical activation ofthe four heart chambers, resulting in suboptimal mechanical performance.It may result during external pacing because such pacing cannotsequentially stimulate the atria followed by the ventricles.

In normal individuals, the atria contract first and the ventriclescontract 0.12 to 0.20 seconds later. Optimal cardiac function is oftenassociated with the proper sequence and timing of electrical activationof the heart. When atrial contraction precedes ventricular contraction,referred to as atrioventricular or AV synchrony, a number of mechanicaladvantages obtain including: a) an increase in the pre-contractionvolume of the ventricles, meaning more blood is available to be pumped;and b) an increase in the pre-contraction ventricular wall tension,which optimizes ventricular mechanical contraction. The decrease incardiac mechanical performance resulting from the loss of AV synchronyis quite variable from person to person; in some persons the decrease istrivial, in others it is profound.

In the arrest described in Table 11, pacing was necessary because ofasystole following the second defibrillation shock. It would not beunusual for a heart, which just suffered through some minutes of theoxygen and nutrient deprivation of a cardiac arrest, to exhibitdepression of electrical and mechanical function. Although externalpacing can stimulate the ventricles and thereby remedy the asystole, itcan not stimulate the atria and ventricles in proper sequence. The lowblood pressure which follows (MP becomes aware of it at 2:56.) may bedue to a combination of both of the aforementioned factors: a) pacemakersyndrome due to loss of AV synchrony; and b) depression of mechanicalfunction post arrest. MP options at that juncture would be: a) lower thepacing rate; b) increasing the pacing rate (to try to stimulate theheart to pump more blood, albeit at a lower pressure); or c) leaving thepacing rate as is. This is a clinical decision, often made bycardiologists and cardiac rhythm specialists. The decision is based onmany factors including the presence, if any, of ongoing rhythminstability (as evidenced by premature beats, for example), the victim'spast medical history, and other clinical parameters.

The logic behind lowering the pacing rate is that after a short periodof pacing for asystole, the heart may recover enough to have its ownpacemaker cells resume functioning. As such a recovery ensues, the cellsmay begin to fire slowly at first, and then have their rate graduallynormalize. However, if external pacing is occurring at a rate which isgreater than the rate at which the heart's pacer cells are firing,ventricular activation will be preempted by the stimulus from theexternal pacer. By lowering the pacing rate, the MP can determine: a) ifsuch a recovery is occurring, and if it is; b) whether allowing thevictim's rate to fall so that the heart's pacemaker cells can “takeover” and so that AV synchrony can resume, results in a more favorableblood pressure.

The decision is a complex one because lowering the heart rate may, insome victims, promote the emergence of greater instability, eitherelectrical (i.e. heart rhythm related) or mechanical (blood pressuredecline). In a worst-case scenario it could lead to another arrest. Thisunderscores the value of having an expert make such decisions.

4.3.1.4 Other MP Decisions Requiring Medical Expertise

Other decisions made by the MP (and unrelated to his interaction witheither the enabler [see Section 4.3.2] or the EMT [see Section 4.3.3])during the sample arrest which require medical expertise include:

a) the choice of which particular electrode pad to use (occurs at 2:03during the sample arrest);

b) defibrillation parameters other than the choice of which electrodesto use, such as energy, pulse configuration, synchronization (occurs at2:19 and 2:33 during the sample arrest);

c) pacing parameters other than the choice of which pacing rate to use,such as pulse width, amplitude, electrode choice (occurs at 2:46 duringthe sample arrest); and

d) the duration of pacing (occurs at 3:05 during the sample arrest).

Other MP decisions which require expertise, might need to be made duringanother arrest, but which were not needed during the sample arrestinclude:

a) when to choose antitachycardia pacing (a form of rapid pacingintended to terminate certain tachycardias) instead of administering ashock;

b) the parameters of antitachycardia pacing (see FIG. 37) including theinitial rate of pacing, the number of paced beats, the interval betweensuccessive paced beats, the interval between last victim beat and firstpaced beat, the pulse width, and the pulse amplitude;

c) the number of antitachycardia pacing attempts;

d) the change, if any, in antitachycardia pacing parameters from oneattempt to the next;

e) the decision, in the case of a victim who is known to have animplantable cardioverter defibrillator or “ICD,” about whether to lethis ICD treat a rhythm abnormality, or whether MP should performpreemptive therapy;

f) the decision about when to begin CPR (see Section 4.5.5.1);

g) the decision about when to terminate CPR;

h) the decision, if on-site physicians and/or EMT are unavailable, aboutwhen to terminate all therapy (see Sections 4.5.3.2 (b), 4.5.5.2 (i) and4.5.7.8.1 (d)).

4.3.2 Enabler Guidance by the MP

The aforementioned MP decisions illustrate the value of the MP fordecision-making capability at the level of an expert cardiac rhythmspecialist. There are other MP actions, which guide the performance ofthe enabler, which are also important. These include: a) properapplication of the electrode pad; b) cardiopulmonary resuscitation; andc) a number of other enabler actions.

4.3.2.1 Enabler Guidance in Proper Application of the Electrode Pad(s)

Proper electrode pad positioning is critical for reasons previouslymentioned. In brief, the shock must be delivered between two electrodesthat are situated, approximately, on opposite sides of the heart. Thegreater the deviation from such positioning, the less the chance that ashock will be successful. Although multi-electrode pads like the fiveelectrode pad and the matrix pad allow the MP to compensate for minor ormoderate errors in pad application or orientation, the MP is less likelyto be able to correct for gross errors.

The MP has multiple options for instructing the enabler in the placementof electrode pad(s). The MP may verbally instruct the enabler as heapplies the electrode pad(s). The MP may visually instruct the enablerby showing him a live video of the victim's torso, upon which MP hassuperimposed visual prompts such as arrows, an outline of the pad, or acartoon version of the pad. If the PU and video boom are situated suchthat superimposition of visual prompts is impractical, the MP may showstill or moving images, kept on file, which illustrate proper padapplication.

During the sample arrest presented in Table 11, the MP guides theenabler in electrode pad application at 2:07. The adequacy of theapplication is assessed at 2:15 and 2:17 (see Table 11 and Section4.5.3.3).

4.3.2.2 Enabler Guidance in Cardiopulmonary Resuscitation

Cardiopulmonary resuscitation is another procedure for which the MP canprovide instruction and guidance. Although not included in the scenarioin Table 11, CPR is a common procedure during cardiac arrests attendedby emergency medical teams. CPR consists of a rhythmic series ofproperly timed chest compressions intended to propel blood through thecirculatory system. In addition, as its name implies, CPR may includemeans to move air in and out of the victim's lungs, a process referredto as ventilation. The person or persons who perform CPR (hereinafterreferred to as “resuscitating person(s)”) may be: a) the enabler; b)anyone else at the scene of the cardiac event; or c) a combination ofthe enabler and another resuscitating person.

The chest compressions are performed by rhythmically pressing down overthe victim's sternum, or breastbone. There are also experimental devicesintended to accomplish a similar result.

Ventilation may be accomplished by properly placing a mask over thevictim's mouth and nose, and squeezing an attached bag which pumps airinto the lungs; the weight of the chest wall and the elasticity of thelungs result in the expulsion of the air without the need for activeexternal intervention. Another ventilation option is so called “mouth tomouth” resuscitation, during which a resuscitating person places hismouth over the victim's mouth (or upon a device interposed between hismouth and the victim's mouth), and blows air into the victim's lungs. Attimes, chest compression is performed without such ventilation.

The need for CPR will depend on both the cause of the cardiac arrest andthe amount of time between the onset of the rhythm abnormality and itsremedy. The success rate for defibrillation without CPR, when thedefibrillation takes place very quickly after the onset of VF, is veryhigh. The longer the elapsed time until defibrillation, the greater thelikelihood that CPR will be necessary. The need for CPR may bedetermined in each of the following ways:

a) CPR will need to be administered if, at the time of the initialrecording, the victim's electrocardiogram shows that the rhythm isnormal, but the blood pressure or oxygen saturation readings are, in theopinion of the MP, unacceptably low.

b) CPR will need to be administered if, post-shock or post-pacing, afteran initially abnormal rhythm has been normalized, the blood pressure oroxygen saturation readings are, in the opinion of the MP, unacceptablylow.

c) CPR will need to be administered if ventricular fibrillation ortachycardia is present which is not responding to electrical shocks.

d) In addition there is more recent evidence to suggest that CPR mayeven have a beneficial effect immediately before the administration of afirst defibrillating shock.

The MP can assist the enabler and/or other resuscitating person in theperformance of CPR in each of the following ways:

a) Using means similar to those for illustrating proper electrode padapplication, the MP may use one of the PU screens 156 to illustratewhere on the chest the resuscitating person must apply pressure. Screenuse may entail images superimposed on that of the victim, or previouslyprepared instructional video materials.

b) The MP may use PU screens 156 to illustrate other aspects of chestcompression including the proper relation between the resuscitatingperson's right and left hands, and the proper body position for theresuscitating person.

c) The MP may coach the resuscitating person during the performance ofchest compression. Such coaching may address the rate of compression andthe vigor with which it is performed.

d) Because the mechanical disruption caused by chest compression ofteninterferes with the ability to record a high quality electrocardiogram,the MP may, from time to time, ask the resuscitating person to suspendchest compression for a few seconds. During such time, the ECG signal isclearer; such interruptions give the MP a better view of the rhythmstatus during chest compression.

e) The MP may also, from time to time, request a pause in chestcompression to recheck the victim's blood pressure. This check mustoccur in the absence of chest compression, since chest compression wouldmask the victim's cardiac performance.

f) Using means similar to those for illustrating proper electrode padapplication, the MP may use one of the PU screens to illustrate properventilation technique.

g) During ventilation, the MP may coach the resuscitating person as tothe proper rate of ventilation. Such coaching would also address the waythat chest compression and ventilation should be coordinated. (Themanner of coordination is different when there are two resuscitatingpersons, as opposed to a single resuscitating person.)

h) Using oxygen saturation data from a sensor which has been applied tothe victim by the enabler, the MP will be able to have some indicationas to the adequacy of ventilation. The MP may use this information togive further guidance to the resuscitating person(s).

i) The presence of airway pressure and flow monitoring sensors withineither a mask (part of the bag and mask ventilating apparatus) or withina device interposed between the resuscitating person's mouth and thevictim's mouth would give the MP another way of determining the adequacyof ventilation (see Section 8.8). The MP may use this information toguide the resuscitating person in his use of the ventilating apparatus.

j) Ventilation adequacy could also be monitored by measuring theimpedance between chest electrodes. Since air has a lower conductivitythan body fluids, as the chest inflates with air, impedance across thechest increases. Certain implanted pacemakers, as are known in the art,perform such measurements within the body, in order to determineventilation status. The MP may use such impedance information to guidethe enabler or other resuscitating person in his use of the ventilatingapparatus (see Section 8.9).

k) Finally, during the performance of CPR, there is enough uncertaintyand hesitancy on the part of all but highly experienced emergencypersonnel, that any reassurance that can be provided during CPR is anasset.

It should be noted that: a) CPR is not required during allresuscitations; and b) even in a situation where enabler and anyone elseat the scene is either unwilling or unable to do CPR (or is unable orunwilling to perform chest ventilation), the ability of the invention toprovide MP expertise in performing the electrical part of theresuscitation and other functions is expected to be of substantialvalue.

4.3.2.3 Enabler Guidance in Other Activities

Other ways in which the MP can guide the enabler, facilitating theperformance of enabler tasks include:

a) guiding the enabler in properly positioning the PU near the victim(occurs at 1:39 during the sample arrest);

b) guiding the enabler in removing victim clothing which may preventaccess to the chest (occurs at 1:56 during sample arrest), discussedbelow in section 4.5.3.3;

c) guiding the enabler in properly applying the blood pressure andoxygen saturation monitoring devices (occurs at 2:48 during samplearrest), discussed below in section 4.5.4.2;

d) guiding the enabler, post EMT arrival, during certain activitiesaimed at making the PU ready for its next use, hereinafter referred toas “housekeeping” (see Section 4.5.7.3, below);

e) guiding the enabler, post EMT arrival, in reattaching a PU to the SU(see Section 4.5.7.4, below); and

f) reassuring the enabler during the commotion and pandemonium that mayaccompany a cardiac arrest (occurs intermittently throughout theMP-enabler interaction).

4.3.3 EMT and Physician Guidance by the MP

The role of the MP expands, once the EMT arrives. MP responsibilitiesthen include:

a) properly identifying the EMT;

b) briefing the EMT about the victim's current condition and the eventsthat transpired during the previous minutes (see Section 4.1.7.2);

c) instructing the EMT in PU operation, if necessary (see Section4.1.7.4.1);

d) providing heart rhythm related diagnostic and management advice, ifnecessary (see Section 4.1.7.4.1);

e) providing pharmacologic advice (see Section 4.1.7.4.2); and

f) providing guidance about cessation of therapy.

As indicated above (see Section 4.1.8), the MP guidance role may alsoinclude providing historical, diagnostic and management advice for thephysician(s) to whom the EMT transfers to victim.

4.4 Time Allocation During the Sample Cardiac Arrest 4.4.1 GeneralConsiderations Regarding Prediction of Duration

Time allocations during the sample arrest are estimates, based on theexperience of the inventor. For some events, such as the time it takesthe MP to correctly read an electrocardiogram, the actual duration isexpected to deviate little from the estimated duration, under mostcircumstances. (Hereinafter, the extent of deviation of actual durationsfrom estimated values is referred to as “the variance.”) For otherevents, such as transporting the PU, substantially greater variance isexpected. Finally, there are certain events such as the duration ofphase seven, where the variance is so great, that no attempt has beenmade to predict event duration.

4.4.2 Enabler Travel Time

Nearly all of phase one in the hypothetical arrest represents the timeit takes the enabler to reach the portable unit. The amount of time willbe a function of both: a) the distance between the victim and the PU; b)the walking/running speed of the enabler; and c) the enabler's abilityto determine where the nearest PU is located. Thirty seconds is assumed;The enabler (assuming a speed of 3.5 miles per hour) is expected to beable to walk approximately 50 yards in this time. It is thereforepossible that phase one could be substantially shorter or longer thanthe allotted 31 seconds.

The return trip, i.e. enabler's transport of the PU from its attachmentto the stationary unit (which may be wall mounted) is also of variableduration. The duration will be determined by: a) the distance betweenthe PU and the victim; and b) the enabler's speed while carrying the PU.If we assume that the enabler transports the unit moving slightly slowerthan he did without having to carry the PU (2.5 miles per hour isassumed), and if we again assume an approximately 50 yard distance, thetime required will be 41 seconds. The total transport time for the PU isthus assumed to be approximately 71 seconds.

4.4.3 Duration of Other Enabler Tasks

Though virtually every event which requires enabler action will vary induration, depending on the particular enabler and event, some eventdurations are less predictable than others. Enabler events whosevariances may be substantial include:

a) enabler's description of the emergency for the MP;

b) enabler's baring the chest of the victim;

c) enabler's application of the electrode pad to the victim;

d) enabler's application of blood pressure and oxygen saturationmeasuring equipment to the victim; and

e) enabler's identifying the victim.

Enabler events with a lesser degree of variance include:

a) enabler's initial decision to help the victim;

b) the audio handshake between the enabler and the MP;

c) removing the PU from the SU; and

d) orienting the PU video boom.

4.4.4 Time Allocation for MP Tasks During Phase Four

Although the duration of individual MP actions is far more predictablethan the duration of either enabler or EMT actions, the number oftherapeutic MP actions required to resuscitate a victim is highlyuncertain. Four MP interventions (two shocks, and two differentbradycardia pacing efforts) were included in the hypothetical arrestscenario presented here. If only a single defibrillating shock had beenrequired to restore a normal rhythm, that restoration would haveoccurred at 2:26 into the arrest. The second shock added another 17seconds; and the need for pacing added another 19 seconds.

The second shock and the pacing thus add another 36 seconds to the timeuntil normal rhythm is restored. These 36 seconds, when added to theaforementioned 71 seconds of variable transport time, total up to oneminute and 47 seconds. Thus more than half of the time until normalrhythm is restored in the current scenario, must be considered to besubstantially variable.

4.4.5 Time Allocation Involving EMT Events

Two EMT related time estimates are also highly variable. The firstconcerns the time that it takes the EMT to arrive. Arrival at 7:25(which is six minutes and thirty five seconds after being called by theMP) is a realistic value for some areas of the United States. The timeof EMT arrival is one of much reduced importance, because the definitivetreatment for the arrest occurs substantially before such arrival. Thesecond highly variable EMT event is the duration of phase seven, and theindividual events which comprise it. Since both the duration and thenumber of phase seven events is highly variable (in part related toregional aspects of EMT policy and procedure), no attempt has been madeto predict the duration of phase seven.

4.4.6 Correction for Simultaneous or Nearly Simultaneous Tasks or Events

Another time-related issue is that certain MP tasks may appear to have asurprisingly short time earmarked for their performance. This is becausesome of these tasks, though listed in the table as sequential, areexpected to be performed simultaneously. For example: during phasethree, the MP could adjust the video boom (allocation in Table 11 is1:54 to 1:56) and instruct the EN (allocated for 1:56 to 2:03)simultaneously. Therefore, the time to do the video adjustments isreally from 1:54 to 2:03, not from 1:54 to 1:56. There are many otherexamples of this overlap phenomenon. There are also instances of eventswhich overlap, and of events and tasks which overlap; in each instances,appropriate adjustment of estimate duration has been made.

4.5 Further Details Concerning Specific Issues During the Sample CardiacArrest

What follows is a discussion of specific events and issues during theaforementioned hypothetical arrest.

4.5.1 Phase One: Amount of Time for Enabler to Reach PU

This is dependent on a number of factors and is discussed in 4.4, above.

4.5.2 Specific Issues During Phase Two 4.5.2.1 Initial and Subsequent MPScreens

At 0:31, as the initial handshake is occurring between the enabler andthe MP, the MP console in the central station immediately changes toreflect the new event. In the scenario described in Table 11, three MPscreens are activated without the MP needing to select them: a) theCommunications Status and Triage Screen, FIG. 25 (first noted in Table11 at 0:31); b) the Portable Unit Deployment Screen, FIG. 27 (firstnoted at 0:51); and c) the Confirmations Screen, FIG. 24 (first noted at0:51). These screens allow the MP to perform the initial operationsduring the early period of his interaction with the enabler.

The MP selection of new screens can occur in one of five ways:

a) Most screens generally have touch-selected choices for each otherscreen that may be needed next. Thus the PU Deployment Screen, FIG. 27,has a GO TO VIDEO CONTROL SCREEN button, since the Video Control Screenis the screen likely to be the one from which the MP works, afterfinishing with the PU Deployment Screen Similarly, the Video ControlScreen, FIG. 28, has an INITIAL ECG SCREEN button, since the latterscreen is likely to follow the Video Control Screen. The Initial ECGScreen, FIG. 29, lets the MP navigate to any one of the three screenslikely to be needed next; the Main Pacing Screen, FIG. 38; the MainDefibrillation Screen, FIG. 33; and the Antitachycardia Pacing Screen,FIG. 37. The Antitachycardia Pacing Screen allows one-touch navigationto the Main Pacing and Main Defibrillation Screens. The Main Pacing andMain Defibrillation Screens each allow one-touch navigation to multipleother screens, each of which deals with one particular parameter ofpacing (e.g. rate) and defibrillation (e.g. energy).

b) Each of the screens which deal with individual pacing anddefibrillation parameters allows rapid transit back to Main Pacing orDefibrillation Screens, by pressing ACCEPT.

c) The Screen Menu, FIG. 44, can be accessed at any time by pressing a“hot key” or keys (e.g. Control, S) on the MP keyboard. When this isdone, the Screen Menu appears on one of the MP touch sensitive screens.This menu provides access to every possible MP screen.

d) The Screen Menu can also be accessed directly from a number of otherscreens, e.g. the Five Electrode Pad Setup Screen, FIG. 31, by a touchsensitive box.

e) The MP may prefer to configure his array of touch sensitive screensso that the Screen Menu is on display at all times.

There are various ways that newly called up screens can displaceprevious ones. These include:

a) having the previously used screen “move” one screen up, rightwards,or leftwards. At a point when live screen capacity is exceed, theoverflow screen is no longer displayed (until and unless it is selectedagain);

b) always displaying certain fundamentally important screens such asConfirmations (FIG. 24), Main Defibrillation (FIG. 33) and Screen Menu(FIG. 43); leaving the remaining touch sensitive screens to be used asneeded;

c) having successively used screens overlay each other. For example,selecting OTHER under Electrodes on the Main Defibrillation Screen (aswas done during the sample cardiac arrest in Table 11), brings up theappropriate electrode setup screen (FIG. 31, for the five-electrodepad). This screen would be superimposed upon the Main DefibrillationScreen until the appropriate selections are made (the α and ε pads)after which the Five Electrode Pad Setup Screen would disappear and theMain Defibrillation Screen would reappear;

d) combinations of the approaches described in (a), (b) and (c).

Note that the number of screens available for viewing may be increasedby: a) simply designing the MP console (FIG. 3) so that it contains morescreens; or b) using screen-in-screen or split screen technology,allowing each physical screen to simultaneously show more than one menuor display.

4.5.2.2 Facilitated Lock Release in the Event of Failure of Handshake #1or #2

As mentioned in Section 4.1.2.3.1, the third level of backup for afailed communication handshake or a failed data/commands handshake isduring the enabler-MP link is for the PU to automatically enter MasterControl State 2. This transfers control of defibrillation and pacing tothe AED/P 128. Master Control State 2 also enables release of themechanism which locks the PU to the SU. The actual release may be: a)fully automatic, whereby entry into Master Control State 2 directlycauses lock release; b) enabler facilitated, in which a voice prompttells the enabler a combination which is entered on a keyboard; or c)enabler facilitated, in which a voice prompt tells the enabler acombination which is used to open a mechanical combination lock.

4.5.3 Specific Issues During Phase Three

4.5.3.1 The MP Interface with Emergency Medical Services

At 0:50 during the sample arrest outlined in Table 11, the emergencymedical team local to the victim is called by the central station. Theymay be called: a) directly by the MP; b) by a CS administrator, or otherperson working with the MP (so that MP's attention need not be divertedfrom dealing with the EN); or c) by computer. As shown in FIG. 27, thePU Deployment Screen, the MP may be provided with access to informationabout:

a) the hospital nearest the victim;

b) the emergency service (fire department, police or hospital based)nearest the victim;

c) estimated arrival times for the nearest emergency service; and

d) telephone numbers for contacting these emergency services.

4.5.3.2 MP Actions During Transport of PU to Victim

At 0:56, the enabler begins moving the PU to the victim's side. (Foradditional discussion and illustration of this event, see Section 5.4.1and FIG. 17.) During this time, if it is established that EN and MP canhear each other well while EN is transporting the PU, MP may furtherdiscuss the situation with EN. During such discussion, MP would:

a) ask for and obtain additional description of the emergency;

b) ask for the victim's identification, if known (This would allow theMP to begin searching one or more databases for further informationabout the victim's past medical history, about a health care proxy (ifany) and about advance directives (if any). In Table 11, theidentification information is obtained later, i.e. during phase five);

c) tell EN exactly how the PU should be situated (i.e. with handles andscreens facing upwards), when placed on the ground or on a stable, flatsurface, very near to the VI;

d) give EN a preview, if time allows, of other tasks to be performed,upon arrival at the VI; and

e) reassure the EN—i.e. that MP is highly experienced, that MP will doall of the decision making, that MP will guide EN through a series ofsimple steps that require no prior medical training, and that anemergency medical team has been summoned.

At 1:42, immediately after EN puts down the PU near the VI, MP willreassess the quality of the audio link between himself and the EN, andmake any adjustments necessary to optimize audibility at both ends. (Foradditional discussion and illustration of this event, see Section5.4.2.2 and FIG. 18B.)

If necessary, MP may ask EN to use a headset, containing both microphoneand earphone, contained in the tool-kit section of the PU. This would beespecially useful in either a noisy environment, or if EN is hard ofhearing. The headset could be wired directly into the PU or could have awireless link to the PU.

4.5.3.3 MP Assessments and Actions, Upon Arrival of the PU at theVictim's Side

At 1:46, shortly after arrival of the MP at the VI, MP asks EN for anupdate on the VI. If the victim had regained consciousness during thetime that EN had been in transit, then the next step would be for the MPto further assess the VI, either by direct observation (checking forvictim motion or speech) or via the EN (who might, upon prompting by theMP, ask questions of the VI). Based on this further assessment, MP woulddecide whether there is a need to expose the victim's chest forapplication of one of the larger electrode pads. If it is anticipatedthat the likelihood of needing pacing or a defibrillation shock issubstantial, then application of one of the electrode pads with thiscapability would be the next step. If, however, such therapy is notlikely to be needed, the Mini-Pads 211, located on the fifth shelf fromthe top of the PU (see FIG. 7B) could be used as standard ECG leads, andbe applied by the EN (under direction of the MP) to the arms and legs ofthe victim. This would provide the MP with an electrocardiographictracing from which he could determine the victim's heart rate andrhythm. In the scenario of Table 11, in which the victim has had acardiac arrest due to ventricular fibrillation, the victim did not (andcould not have) regained consciousness; the EN thus informs the MP thatthe victim is unconscious.

At 1:54, after adjustment of the PU video camera, if the MP determinesthat the PU location is sub-optimal, e.g. too far from the victim, MPwill inform EN of the need to reposition the PU.

At 1:56, the instruction in exposing the victim's chest includes tellingthe EN: a) the reason for exposing the chest; b) that there is ascissors in the tool-kit, which can be used, if necessary; and c) theextent of the area which needs to be bare, to accommodate the electrodepad(s). The MP may display instructional video materials on the PUscreen 156 which illustrate the location of the scissors within thetool-kit (FIG. 7A) and the proper approach to clothing removal. Whendisplaying instructional video materials, the MP would work from VideoControl and Instruction Screen, FIG. 28 (discussed below).

Based on MP observations of the victim while EN is exposing the chest,MP decides which of the electrode pads contained in the tool-kit bestsuits the victim. In the current scenario electrode pad 204B is selected(at 2:03) which could be used on a male, or a female who did not havelarge breasts. This pad has five large defibrillating electrodes andseven small ECG electrodes. The choice of pad is based on MP judgmentand experience.

At 2:15 and at 2:17 during the sample arrest, the MP assesses how wellthe pad has been applied to the victim's skin by observing (at 2:15) thedisplay of impedance measurements for each electrode, and by observing(at 2:17) the multi-lead ECG signal. These are displayed in the centralstation on the Initial ECG Screen (FIG. 29, discussed below) and on thededicated ECG screen 302 (FIG. 3). According to techniques known in theart the system would optimize the ECG signal; the MP would have theoption of changing the system-selected parameters (e.g. the gain) orotherwise adjusting the signal. The MP might tell the enabler to pressdown over one or more sections of the pad if the MP observes highimpedance readings or low amplitude ECG recordings corresponding to suchan area.

4.5.3.4 Enabler Headset Handshake

The enabler may need to use a headset-microphone combination 168,contained in the tool-kit, if either he or the MP are not hearing eachother well. If the headset-microphone is wireless, then its properlinkage to the PU may be confirmed by: a) a formal handshake routineanalogous to the first three layers of the enabler-MP handshake (seeSections 4.1.2.3.1 through 4.1.2.3.3 and Table 7); or b) a much simpleraudio handshake, analogous to layer three only, primarily intended toallow for the adjustment of gain controls on each end. The simplerhandshake described in (b) would be the approach if theheadset-microphone had a wire connection to the PU.

4.5.4 Specific Issues During Phase Four:

4.5.4.1 Wide Variety of MP Choices for Defibrillation and PacingParameters; Central Station Screens which Correspond to these Choices

The MP has access to a wide variety of treatment choices concerning thedetails of defibrillation and pacing; The choices selected during thesample arrest represent only a small fraction of the available options.

During the sample arrest, when defibrillation was necessary, the MPinitially chose default values of shock parameters; When a second shockwas necessary, the MP chose to alter the electrode pair through whichthe defibrillation energy was directed. Other MP options concerningdefibrillation parameters include: a) changing defibrillation energy(FIG. 34, Defibrillation Energy Screen); b) changing shocksynchronization (FIG. 35, Synchronization Screen), i.e. the precisetiming of energy application; and c) changing the shape of thedefibrillation pulse contour (FIG. 36, Pulse Contour Screen).

During the sample arrest, when pacing was necessary to treat a slowheart rhythm post-shock, the MP initially chose default values of pacingparameters; He later decreased the pacing rate. Other MP optionsconcerning pacing parameters include: a) changing the pacer amplitude(FIG. 39, Pacer Output Screen); and b) changing the pacer pulse contour(FIG. 36, Pulse Contour Screen).

These central station screens, and others are discussed below in section6.

4.5.4.2 MP Instructs Enabler in the Application of Blood Pressure andBlood Oxygen Saturation Devices

At 2:48 during the sample attest, once bradycardia pacing has commenced,the MP must determine the victim's blood pressure and blood oxygensaturation. The MP thus gives audio instructions to the enabler. The MPmay also display instructional video materials on the PU screen 156which illustrate the location of these two devices within the PUtool-kit (FIG. 7A) and the proper technique of their application to thevictim. When displaying instructional video materials, the MP would workfrom Video Control and Instruction Screen, FIG. 28 (discussed below).The results of blood pressure and oxygen saturation determinations aredisplayed on screens 304 and 306 respectively, on the MP console in thecentral station (FIG. 3).

4.5.5 Specific Issues During Phase Five 4.5.5.1 Possible Performance ofCPR During Phase Five

Once the blood pressure and blood oxygen saturation information isavailable, the MP will be able to make a determination as to the need,if any, for cardiopulmonary resuscitation. As was discussed above insection 4.3.2.2, CPR will need to be administered if, after the rhythmhas been optimized, the blood pressure or oxygen saturation is, in thejudgment of the MP, unacceptably low.

It is also possible that CPR would be needed during phase four. As wasdiscussed above in section 4.3.2.2, this would be the case if either: a)ventricular fibrillation or tachycardia was present which was notresponding to electrical shocks; or b) the MP determined that theadministration of CPR before giving a shock was desirable.

4.5.5.2 Multiple Possible Types and Sources of Victim RelatedInformation

Once the victim has been identified, the MP may obtain informationabout:

a) the victim's past medical history;

b) the victim's last or baseline electrocardiogram;

c) the victim's current medication names and doses;

d) the victim's allergies, drug and non-drug;

e) about an implanted pacemaker or defibrillator, including themanufacturer, model and programmed settings;

f) the names and telephone numbers of one or more of the victim'sphysicians;

g) the names and telephone numbers of hospitals or clinics where thevictim may have been treated;

h) information about victim's next-of-kin; and

i) information about health care proxy and advance directive, if any,i.e. legal documents which may specify who and how health care decisionsare to be made for this victim, if victim cannot participate in suchdecisions.

Such information may come from a number of databases or sourcesincluding:

a) a database maintained by the central station (which may be located(i) at the central station, (ii) at one or more off-site locations, or(iii) both);

b) the victim's physician(s);

c) hospitals or clinics where the victim had been treated;

d) private corporations or other business entities which may maintainsuch databases; and

e) government based data archives including Medicare, Medicaid, andother state and foreign sources.

f) a card or other item carried by the victim onto which medicalinformation has been encoded, which may be decoded by apparatus withinthe PU.

The encoding, transmission, retrieval, display and storage of theaforementioned information would be carried out in accordance with allgovernment regulations regarding privacy.

Although victim identification during the sample arrest occurs duringphase five, it could occur as early as phase three or as late as phasesix; or not at all.

4.5.5.3 Multiple Possible Means of Tracking Local Emergency Services

At 3:36 during the sample arrest, the MP informs the enabler of theestimated time of arrival of the local Emergency Medical Team. In apreferred embodiment of the invention, the Portable Unit DeploymentScreen (FIG. 27) displays this estimate. Such information may beobtained:

a) from an EMT estimate which is inputted directly to the centralstation;

b) from a verbal estimate supplied by the EMT;

c) from (i) global positioning (GPS) equipment within an EMT vehicle,(ii) a computer program which estimates travel time (such as Microsoft®Expedia™ Trip Planner 98), and (iii) a computer on which this programruns; whereby GPS-derived data regarding EMT location is inputted intothe computer which is running the travel time program, and the computersupplies the central station console with estimated arrival timeinformation, which is displayed on the Portable Unit Deployment Screen(FIG. 27); or

d) from a non-automated version of (c), in which the location of the EMTis manually entered into the aforementioned travel time program.

Using any of these methods, the MP may track the location of more thanone EMT and thereby facilitate the deployment of such teams by:

a) informing an emergency medical team of the location of another teamor team(s);

b) directing the team with the shortest estimated arrival time toproceed to the scene of the emergency;

c) directing the most well equipped team to the scene of the medicalemergency;

d) using information about the location of a team and how well equippedit is to select the most appropriate team or team(s).

4.5.6 Phase Six: Specific Issues During Phase Six 4.5.6.1 AnalogousAspects of the Enabler-MP Link During Phase Two, and the EMT-MP LinkDuring Phase Six

As was discussed in 4.1.6.2, the four handshakes which constitute theEMT-MP link are analogous to the four handshakes which constitute theenabler-MP link (see also Tables 7 and 9, above).

Another analogous feature resides in the third level of backup, in theevent of failure of a handshake in layer #1 or #2. In each of the twolinks, the system is designed to allow a “probably appropriate” user tohave access to the PU; i.e. it gives the “benefit of the doubt” to theperson desiring access. In each of the two links, the primary mode ofoperation is for the MP to approve the release of the unit, either: a)physically, with the PU to be removed from the SU, following theenabler-MP link; or b) electrically, to be controlled by the EMT,following the EMT-MP link. The secondary mode is to allow release of theunit without MP approval, as described above and below, in the event ofhandshake failure.

In the event of a failure of either of the first two handshakes betweenenabler and MP, the enabler can gain access to the PU without the MPhaving to release the unit. In this case, the PU (functioning in MasterControl State 2, independent from the CS) informs the enabler of thecombination to a lock, mechanical or electrical, which releases the PUfrom the SU; In an alternative embodiment, the PU could be automaticallyreleased in the event of handshake failure in the first two layers ofthe enabler-MP link.

Similarly, in the case of the EMT-MP link, as was discussed above inSection 4.1.6.2.1, a failure of either of the first two handshakes letsthe EMT bypass the usual MP-based password approval; The PU itself willaccept a pre-programmed EMT password, without MP approval, in the eventof an unsuccessful communication or data/command handshake.

4.5.6.2 Timing of EMT Arrival

During the sample arrest, the EMT is called at 0:50 and arrives at 7:25.This constitutes an elapsed time of six minutes and thirty five seconds,which is a reasonable estimate by large city standards

One way to view the effectiveness of the invention is to consider howmuch time was saved by instituting life-saving therapy (i.e.defibrillation) before the EMT arrived. It is possible to estimate alower boundary for this parameter.

4.5.6.2.1 Time Saved by Using the Invention: Estimation of the EarliestPossible Defibrillation by EMT, Without the Invention

A number of assumptions must be made to perform this estimation:

a) Assume that EMT had been called at the moment of button press, i.e.0:31 (see Table 11). This assumes that the amount of time required topress the button is the amount of time required to call 9-1-1.

b) Assume that six seconds are needed to describe the event to the EMTdispatcher. This is the same estimate used for the sample arrest. Thisputs their dispatch at 0:37.

c) Assume (as was assumed during the sample arrest, above) that sixminutes and thirty five seconds is the time from EMT dispatch until EMTarrival. This puts their arrival time at 7:12 after enabler noticed thevictim

d) Assume that from the moment of EMT arrival until they assess thevictim, remove or cut the victim's upper garment, hook up theirdefibrillator, diagnose VF, charge their defibrillator and finally shockthe VF, is 30 seconds, i.e. an extremely rapid performance. This putsthe time of first shock at 7:42 after enabler noticed the victim.

e) Assume that the first shock was effective. The only reason to makesuch an assumption (aside from trying to come up with the lowestpossible estimate of the time to EMT termination of VF) would be if theEMT did a substantially better job of attaching and orienting theelectrode pad than did the MP/enabler. In reality, it is likely thatMP/enabler shocks will be more successful than EMT shocks, because theMP/enabler shocks will be administered much sooner than the EMT shock.The time of the shock when the invention is not used is 7:42; the time(of the [definitive] second shock) when the invention is used is 2:40(Table 11).

Working with the aforementioned five assumptions, definitive therapycomes nearly five minutes sooner (2:40 vs. 7:42), using the invention.It is estimated that cardiac arrest mortality increases by roughly tenpercent per elapsed minute without therapy. Therefore, using theseextremely optimistic estimates for EMT performance, the invention wouldbe expected to cause an approximately 50% reduction in the mortalityfrom a cardiac arrest.

4.5.6.2.2 More Realistic Estimates for EMT Defibrillation

Two issues make the aforementioned estimate of EMT performance (withoutthe invention) especially optimistic:

a) Assumption (e). Because ventricular fibrillation is assumed to havebeen going on for more than seven minutes before EMT arrival (withoutthe invention), there is a good chance that the first shock will not besuccessful. Multiple shocks might be required. A period of CPR mightneed to precede one or more of the shocks. And, it is possible that asuccessful shock at this late time might not occur until afterintravenous medication has been administered. If this is the case, evenmore time is lost.

b) In the current analysis, it has been assumed that the endpoint forresuscitation is the time of termination of VF. If, instead, theendpoint of the resuscitation process is assumed to be the moment when asurvivable blood pressure is restored, then there may be an even greaterdisparity between the resuscitation time without the invention, comparedto that with the invention. The prolonged time of abnormal heart rhythm(without the invention) is again the reason. During the minutes when theheart is in VF, unless CPR is performed, the blood pH falls, the levelof potassium in the blood rises, and the heart muscle cells suffer fromoxygen deprivation and accumulation of toxic metabolites. The result isthat even when VF is terminated, the heart's mechanical performance isinitially poor. The longer the period of VF without any therapy, thegreater the time until good mechanical performance can be restored, ifever. Thus, the five minute delay until the definitive shock isadministered (when the invention is not used), causes additional delayin the restoration of proper cardiac mechanical performance.

4.5.7 Specific Issues During Phase Seven 4.5.7.1 Overview of PhaseSeven: Two Sequences of Events

Two sequences of events occur during phase seven of the sample cardiacarrest. The first involves transfer of control to the EMT. The secondinvolves replacement of the PU.

4.5.7.1.1 Analogous Aspects of Phase Seven and Phase Three

The first and most important sequence of events during phase seven,parallels events during phase three (in which the enabler obtains thePU, and is guided by the MP in its setup), and involves EMT obtainingcontrol of the PU, with MP guidance of the EMT. This sequence of eventsincludes:

a) release of the PU to the EMT (see Section 4.1.7.1);

b) presenting the details of the event with the EMT (see Section4.1.7.2);

c) instructing the EMT in the operation of the PU, when such instructionis needed (see Sections 4.1.7.2 and 4.1.7.4.1); and

d) attaching a new PU to the victim, (occurs only when EMT brings a newPU and it is to be attached to the victim; see Section 4.5.7.2.2).

The second sequence of events during phase seven is analogous to atime-reversed version of phase three events, and involves attaching a PUto the SU. Such phase seven events include:

a) replacing the non-disposables in the PU tool-kit, when necessary (seeSection 4.5.7.3.4);

b) retracting the video boom and the PU antenna, when necessary (seeSection 4.5.7.3.5);

c) transporting a PU back to the SU (see Sections 4.5.7.2.1 and4.5.7.3.6); and

d) attaching this PU to the SU (see Section 4.5.7.4.3).

“When necessary,” above, pertains only to scenarios in which the old PUis returned to the SU.

The phase three events which are paralleled by the aforementioned phaseseven events are discussed above in Sections 4.1.3.1 and 4.5.3.2; andare listed in the phase three portion of Table 11.

4.5.7.1.2 Two vs. One Portable Unit at the Arrest Scene

There is complexity in describing PU deployment because: a) the EMT mayor may not bring along another PU; and b) in each of these twosituations, the old PU may or may not be returned to the SU. Thisresults in two independent choices, each with two possible outcomes; theresult is four possible options, described below and in Table 12.

TABLE 12 Deployment of the Old PU After EMT Arrival Option Section OldPU To: New PU To: Housekeeping 1 4.5.7.2.1 Victim SU Not Required 24.5.7.2.2 SU Victim Required 3 4.5.7.7.1 SU No New PU Required 44.5.7.7.2 Victim No New PU Not Required

If the EMT brings a replacement PU, there are two ways of deploying theold and the new portable units, hereinafter referred to as “option one”(old PU remains attached to victim; described in Section 4.5.7.2.1) and“option two” (old PU returned to SU; described in Section 4.5.7.2.2).These two options are further discussed below in Sections 4.5.7.3through 4.5.7.6, and 4.5.7.8.2.

If the EMT does not bring a replacement PU there are two ways ofdeploying the old PU, hereinafter referred to as “option three” (old PUis returned to SU; described in Section 4.5.7.7.1) and “option four”(old PU remains attached to victim and is transported to hospital;described in Section 4.5.7.7.2). These latter two options are furtherdiscussed below in Sections 4.5.7.3, 4.5.7.4, 4.5.7.5.1 and 4.5.7.8.2.

4.5.7.2 Two Portable Units Available: New Versus Old PU as theReplacement Unit

In a preferred embodiment of the invention, the PU, in between events,is detachably mounted on a stationary unit which is permanently mountedon a wall at approximately eye level as shown in FIG. 2A. Before theenabler and EMT leave the scene of the arrest, it is therefore desirablethat one of them attaches one of the portable units to the SU. The otherPU is transported to the hospital, attached to the victim.

4.5.7.2.1 Option One: Old PU Remains Attached to the Victim; New PU tobe Attached to the Stationary Unit; Transportation of the New PU to theSU

This is the scenario which is assumed to occur during the sample cardiacarrest, referred to in Section 4.1.6. (The scenario in 4.1.6.1, choice(b), also entails leaving the old PU attached to the victim.) It is theprocedurally simpler than the scenario described immediately below(Section 4.5.7.2.2) in which the old PU is left behind, and the new PUis attached to the victim.

Unless otherwise specified, the present remarks refer to embodiments ofthe invention which have a stationary unit.

The current scenario (new PU left at the emergency scene) requires:

a) that the EMT brings another PU to the emergency scene;

b) that during a future emergency, the MP can match the new PU serial oridentification number, with the PU location (This matching process ishereinafter referred to as “PU localization.”);

c) that the new PU is transported to the SU; and

d) that the new PU becomes physically attached to the SU (discussed inSection 4.5.7.4, below).

There are a variety of ways that PU localization may be accomplished:

a) The EMT may simply read the serial number of the new PU to the MP,who would enter it into the central station computer.

b) The EMT may press the emergency button on the new PU.

The new PU would then transmit its serial number to the MP who couldenter it into the central station computer. Various means are availableto let the MP know that the button press on the new PU is intended toindicate localization at the same site as the old PU, and does notconstitute a different emergency.

c) The new PU may be programmed to transmit its identificationinformation when it gets attached to the SU (see below), with the SUsupplying the location identifier.

d) In a preferred embodiment of the invention, a global positioningsystem within the new PU would notify the CS of its location. Thisnotification may be automatic or initiated by button press, and wouldoptimally occur shortly after EMT arrival.

As indicated above, the new PU must be transported to the SU, to preparethe site for a future emergency. If enabler is the person transportingthe new unit, he should know the SU location. If someone other thanenabler is transporting the unit, either the MP or the enabler mayinform him of the SU location.

4.5.7.2.2 Option Two: New PU is Attached to the Victim; Old PU to beReattached to the Stationary Unit

This is the scenario which is referred to in Section 4.1.6.1, choices(a) and (c).

This scenario (old PU left behind) requires:

a) that the EMT brings another PU (the “new PU”) to the emergency scene;

b) that the EMT presses the emergency button on the new PU and goesthrough an abbreviated handshake routine to link the new PU with the CS;

c) that the old PU be detached from the victim;

d) that the new PU be attached to the victim;

e) that there be an abbreviated handshake routine to confirm the linkbetween the new PU and the victim;

f) that certain “housekeeping” functions be performed to make the old PUready for future re-use (discussed in Section 4.5.7.3, below);

g) that the old PU is transported to the SU; and

h) that the old PU becomes physically reattached to the SU (discussed inSection 4.5.7.4, below).

The handshake which follows the button press to link the new PU to theCS is conceptually similar to the enabler-MP link described in Section4.1.2, but simpler. The reasons for the simplification are: a) AED/Pbackup is not needed; b) other backups are simpler as well, since theEMT and the MP are already in communication via the old PU; and c) thefourth layer of handshake, the informational handshake, is markedlysimplified, compared to its counterpart during the enabler-MP handshake(when the enabler described the emergency to the MP); the onlyinformation that the EMT needs to give is the serial or identificationnumber of the new PU, if it was not transmitted automatically at thetime of new PU button press.

The universal connectors, discussed below, allow quick and easydetachment of an electrode pad from the PU, and reattachment of anotherelectrode pad to the PU. In the current scenario, electrode pad 204B(five large defibrillating electrodes, seven small ECG electrodes; FIG.5B) was used). This pad utilizes female universal connector “UC” 218Awhich connects to male UC 220A of the PU (FIG. 7B). To switch portableunits, the EMT would:

a) disconnect the female and male universal connectors 218A and 220A onthe new PU;

b) disconnect the female and male universal connectors 218A and 220A onthe old PU (thereby briefly detaching the victim from the PU and leavinghim briefly unmonitored);

c) attach the female UC 218A which terminates the cable extending fromthe electrode pad attached to the victim, to the male UC 220A whichterminates the cable extending from the tool-kit (FIG. 7B) of the newPU, thereby re-establishing victim monitoring; and

d) attach the female UC 218A which terminates the cable extending fromthe unused electrode pad, to the male UC 220A which terminates the cableextending from the tool-kit of the old PU, thereby making the old PUready for re-use.

The EMT and/or MP confirm that the victim's electrode pad is properlyattached to the new PU with a handshake which is analogous to butsimpler than the third layer of the victim-MP link (see Section4.1.3.2.1 above). Simplification results from the fact that theelectrode pad was already shown to be functional and properly placedduring its earlier use. The handshake is performed by: a) observing theelectrocardiogram tracing on the new PU; and b) going to the Initial ECGScreen (FIG. 29) and confirming that the impedance values (which assessthe quality of the pad-victim interface) are in proper range.Troubleshooting for this activity involves the backups presented abovein Table 9 (Section 4.1.3.2.1).

The brief period of absence of victim monitoring is a disadvantage ofthis approach, compared with the approach described in Section4.5.7.2.1, in which the old PU is never detached from the victim.However, a ‘Y’ connector arrangement, in which the some or all of theelectrodes in the pad are in electrical continuity with a second cablewhich terminates in a second female connector, could prevent thisproblem. This second cable would be attached to the new PU before thefirst cable would be detached from the old PU; Accordingly, there wouldnever be a time when the victim was not attached to at least one of theportable units.

The process of preparing the old PU for reuse and of reattaching it tothe SU is described below (see Sections 4.5.7.3 and 4.5.7.4).

4.5.7.3 Housekeeping Activities Before Returning the Old PU to the SU;Transportation of the Old PU to the SU

If the old PU is to be left at the scene of the emergency (as occurs inoptions two and three), the ideal approach would be to do as many thingsas possible to restore it to a ready-to-use condition. Such restorationactivities are herein referred to as housekeeping activities. Theelectrode pad is generally not reusable; the same may be true of theoximetry sensor. In a preferred embodiment of the invention, extra padsand oximetry sensors (if disposable) are stored in the miscellaneoussection 177 of the tool-kit of the PU (FIG. 7A) and can be used toreplace these disposable items (see Section 4.5.7.3.3). Used,non-disposable items must be returned to the tool-kit (see Section4.5.7.3.4).

4.5.7.3.1 MP Role During Housekeeping

The MP role in housekeeping activities involves:

a) confirming proper electrode pad replacement;

b) guiding on-site person(s) in the performance of certain activities;

c) inspecting the PU during or after these activities, to confirm theirproper performance; and

d) retracting the video boom, once inspection is complete (see Section4.5.7.3.5).

e) making sure that after the event is over, a replacement PU isproperly positioned, functioning and supplied.

4.5.7.3.2 Choice of Individual to Perform the Housekeeping Activities

The choices for who performs the on-site housekeeping activitiesinclude:

a) the EMT;

b) the enabler;

c) another bystander at the scene of the emergency, other than theperson who has functioned as the enabler; and

d) a person (arriving after the medical emergency) from, or related tothe same organization that includes the central station and/or themedical professional (see section 4.6).

e) combinations of the above.

We shall assume, in the sections that follow, that the enabler performsthis function. The MP would make sure that at least one of these personsis selected, and that the person or persons responsible for theseactivities: a) is aware of their responsibilities; and b) carries themout.

4.5.7.3.3 Electrode Pad Replacement; Oximetry Sensor Replacement

In the case of option two, when a new PU is substituted for the old one,electrode pad replacement should have already been performed (see fourstep process in Section 4.5.7.2.2), using a replacement pad from thetool-kit of the new PU. If an EMT who is under time pressure does notperform the fourth step listed in Section 4.5.7.2.2 (i.e. replacing thepad on the old PU), the enabler (or person performing the housekeepingfunctions) would do it at this point. (The same replacement processwould occur in the case of option three [EMT does not bring a PU andleaves the PU at the arrest scene], see Section 4.5.7.7.1.) In order toaccomplish this task, the enabler must: a) disconnect the used pad; b)remove a new pad from the tool-kit; and c) connect the new pad.

The old pad is removed by disconnecting the female universal connector218A (to which the pad is attached) from the male UC 220A. A new pad,labeled to indicate that it is the same one which has been used, isremoved from the tool-kit and connected to universal connector 220A.

The MP has two ways of knowing that this procedure was performedproperly: First, the female UC (the UC which comes from the electrodepad) has certain pairs of pins which are electrically common (see belowand see FIGS. 56B-56F). The UC for each of the different types of padhas a different pair of electrically common pins. Therefore, byobserving the impedance readings for the circuits involving thepreviously used pad, it is possible for the MP to know: a) that the oldpad was disconnected; b) that the new pad was connected; and c) that thecorrect pad was connected. Furthermore, in a preferred embodiment of theinvention, the MP can know that the enabler did not simply reconnect theold pad, as follows: The electrical continuity created by the conductivestrip 266 within the pad backing 260 (see Section 3.2 and FIG. 5E)distinguishes an unused pad (with intact backing and conductive strip)from one with the backing removed.

Second, the MP can use the video camera of the old PU to observeenabler's performance. This may be useful if enabler is unsure aboutwhich pad to select, or how physically to connect or disconnect the UCs.The MP can also use the video camera to make sure: a) that the enablergently pushes the pair of UCs 218A and 220A and ribbon cables 212A and222 onto the appropriate shelf (166A) in the upper portion of thetool-kit; and b) that the enabler then places the newly attached pad onthe appropriate shelf in front of the UCs and cables. However, althoughvisual confirmation is valuable, the ultimate verification of a properlycompleted pad replacement is electrical, as described above.

The oximetry sensor 174 would also be replaced at this time, if it isthe disposable type, by simply disconnecting the old one (if not alreadydone by the EMT) and replacing it with a spare from the tool-kit.

4.5.7.3.4 Replacement of Non-Disposable Items

The MP would make sure that the enabler places the blood pressure cuff172 and scissors 170 in the appropriate compartments of the PU tool-kit(FIG. 7A). If the oximetry sensor 174 is the non-disposable type, it toowould be returned to the tool-kit at this time.

If either the wireless headset 168 or the telephone cable 176 has beenused, they now need to be replaced. The MP can re-attempt communicationby means which do not require the headset (e.g. via PU speakers 146 andPU microphone 148, or via PU handset 150) or the telephone cable; Butthe MP must first tell enabler the remainder of the replacement plan, incase communication is immediately lost or later interrupted, once theseitems 168 and 176 are returned to the tool-kit. The remainder of theplan involves: a) closing the tool-kit door; b) transporting the PU backto the SU; and c) attaching the PU to the SU (as described below in4.5.7.4)

MP confirmation that these steps have taken place is either based onenabler's statement to this effect, or by observation via video camera.If communication is terminated (because it was based on the headsetand/or the telephone cable) before all enabler tasks are confirmed, theycan be confirmed once communication is re-established, after the PU isreturned to the SU.

4.5.7.3.5 Video Boom and Antenna Retraction Prior to Moving the PU

Prior to moving the PU, the MP must retract the video boom 112 so thatthe video camera 154, if it has been deployed, is returned to a positioninside of the PU. This protects it from damage during the move. This canbe performed once the inspection process is complete.

Prior to enabler's moving the PU, the MP may instruct the enabler tolower the PU antenna 162, if it has been raised. MP may inform theenabler that if communication disruption occurs once the antenna islowered, then enabler's choices are to: a) raise the antenna and pressthe emergency button; or, b) return the old PU to the vicinity of theSU, and then attempt to re-establish communication, by button press,with or without antenna extension. In a preferred embodiment of theinvention, antenna movement is directly controlled by the MP, bymechanical means as are known in the art. If MP wishes to avoid thepotential disruption in communication that might occur as a result ofantenna lowering, he may allow the PU to be transported withoutretracting the antenna.

4.5.7.3.6 Transportation of the Old PU to the SU

If the old PU is being returned to the SU, the MP, as soon as the videoboom is retracted, informs the enabler that he may return the PU. Ifenabler is the person returning the unit, he should know where it camefrom. If someone other than enabler is returning the unit, either the MPor the enabler may inform him of the SU location.

4.5.7.4 Attachment of the PU to the SU

Such attachment occurs during option one (Section 4.5.7.2.1), option two(Section 4.5.7.2.2) and option three (Section 4.5.7.7.1).

4.5.7.4.1 Who Performs the Attachment?

The choices for who attaches the new or old PU to the SU are identicalto those for the performance of the housekeeping functions, discussedabove in Section 4.5.7.3.1. Again, we shall assume that the enablerperforms this function.

4.5.7.4.2 Mechanical Issues in the Attachment Process

FIG. 9 shows that the SU has a shelf in its lower portion, whichsupports the PU. Replacing the PU requires sliding it across the shelf,from the front of the shelf to back of the shelf; so that the powerconnector 186 on the PU (FIG. 8) engages its counterpart, powerconnector 192 on the SU. In similar fashion, telemetry connector 188 onthe PU engages its counterpart 190 on the SU. Meanwhile, the lockingprojection 194, extending from the SU will engage the PU receptacle andelectromagnetic lock within the SU.

A variety of mechanical mechanisms (not shown in FIG. 8 or 9) mayfacilitate the attachment procedure:

a) The SU shelf may include small wheels or cylindrical rollers on itssurface, to facilitate sliding the PU back toward the vertical part ofthe SU.

b) Alternatively (or, in addition), the PU may also include such smallwheels or rollers on its under-surface. (The under-surface of the PU isdefined as the surface opposite the that which contains the handle shownin FIG. 8.)

c) Locator pins may project from the SU and enter receptacles in the PUto help guide the PU as the enabler pushes it into place.

d) A narrow “wall” at each edge of the SU shelf would help guide the PU.

e) Grooves in the SU shelf with matching projections on theunder-surface of the PU, or the inverse arrangement with grooves in thePU under-surface and matching projections on the SU shelf, would helpguide the PU.

The MP may facilitate the attachment procedure by informing the enablerof the mechanical guides which help align and position the PU as itreturned to the SU.

4.5.7.4.3 Endpoint for PU-SU Attachment

The goal for this step is to have the enabler return the PU to theposition in which it is attached to the SU, and in which it is designedto remain, in between deployments: hereinafter referred to as the “homeposition.” In the home position:

a) each of the sensor switches 178 has its central dowel depressed by anappropriate amount;

b) each of the PU feet 180 is resting in its proper position withrespect to the SU shelf;

c) the PU telemetry connector 188 properly engages its counterpart, theSU telemetry connector 190;

d) the PU power connector 186 properly engages its counterpart, the SUpower connector 192; and

e) the SU locking projection 194 properly enters and engages PUreceptacle and electromagnetic lock 182.

The MP may gauge the progress and adequacy of the PU-SU attachmentprocess by monitoring a number indicators available to him: Theseindicators include the following:

a) The PU sensors switches 178 (FIG. 8, Section 2.3) will provideposition and orientation information as the PU nears its home position.As the PU nears the home position, the central dowel within the sensorswitch is depressed, providing position information. Proper orientationof the PU is deduced when multiple sensor switches show identicaldegrees of depression (to within the limits of measurement)simultaneously. The greater the number of sensor switch positions, andthe greater the number of sensor switches, the more detailed is theposition and alignment information available to the MP. Furthermore,when three or more sensor switches are present, their placement in anynon-linear pattern will give the MP information about misalignment of“pitch” or “yaw.”

b) The MP will know when the PU telemetry connector 188 (FIG. 8)properly engages the SU telemetry connector 190 (FIG. 9) as the homeposition is approached.

c) In the home position, the SU locking projection 194 (FIG. 9) engagesthe electromagnetic locking mechanism 182 within PU. Sensors within thelocking mechanism can inform the MP of proper engagement.

d) Other sensors (not shown): (i) mechanical, (ii) photoelectric, (iii)laser or (iv) continuity, may be positioned in the SU shelf 108, the PUbottom and the PU back. They would give the MP additional PU positioninformation, as the PU slides toward the home position.

e) A grid, cross, dot, mark, pattern, picture, or mirror could be placedon a wall opposite the PU (i.e. the wall which the screen side of the PUfaces). Sighting through the video camera would allow for the detectionof misalignament, though this could only occur once the enabler hasmoved out of the way. The MP could also use a combination of theseindicators.

The MP would inform the enabler, if MP has evidence of eithermisalignment or insufficient advancement of the PU, and would tellenabler of suggested corrective action.

It would also be possible to guide the enabler automatically (e.g. withvoice prompts) without MP involvement. This approach would be useful: a)in the event of communications failure (see Section 4.5.7.5, below); orb) if (i) a new PU was being mounted and (ii) the PU localizationprocess (see Section 4.5.7.2.1) had not yet been performed.

There are a variety of approaches to informing the enabler as to whenthe PU has been properly and adequately advanced, and is correctlysituated in the home position:

a) The MP may tell the enabler that the PU is properly positioned.

b) An audible mechanical click may be heard when the lock engages.

c) The PU may emit a tone or a voice prompt indicating properattachment.

d) One or both of the screens 156 may flash and/or provide a textmessage indicating proper attachment.

e) Resistance to further PU motion (either towards or away from the backwall of the SU) could serve as an indicator.

4.5.7.4.4 Checking the PU Post-Attachment

Attaching the PU to the SU initiates a diagnostic checking routine thatis described below (see Section 4.6.2). When this occurs, the PU entersMaster Control State 4 (see table 1 and Section 1.3.1.2) The check isperformed whether the attached PU is an old or a new one. Electricalfunctioning within the PU and the SU, as well as the integrity of thePU-SU connections are assessed.

Using the video camera 154, the MP may also perform a visual check whichincludes: a) an inspection of the PU and SU; and b) an assessment of thefunctioning of the PU screens 156 (see Section 4.6.2)

4.5.7.5 Choices in the Event of Communications Failure During PhaseSeven;

Once the EMT has arrived and assumed control of the PU, a communicationsfailure with the central station would not be nearly as momentous as oneprior to EMT arrival.

If a break in communications occurs, the MP, immediately aware of it,makes efforts to restore the link using techniques referred to above, inSection 4.1.2, and below. The PU would: a) notify the EMT (by voiceprompt, screen message or text printout), who would have multiplecommunication possibilities (see Section 4.5.7.5.1, below); b) presentEMT with an audio, video or printed summary of the arrest (containingthe information stored in the PU, i.e. the first six of the thirteenitems listed above in Section 4.1.7.2), if MP had not completed thistask before communications interruption; and c) present EMT with anaudio, video or printed version of PU operating instructions, if the MPhad not completed this task before communications interruption.

4.5.7.5.1 EMT Communications Choices Using Only One Portable Unit

If he becomes aware of a communications failure between the PU and theCS, the EMT has the following choices:

a) The EMT may make no active effort to restore communication, allowingMP to perform this function.

b) The EMT may access a simplified version of the Communications andTriage Screen (FIG. 25) from the truncated Screen Menu, via PU screen156. This would allow the EMT to chose “GO TO AED/P”. Such a choicecould be useful if the EMT is busy doing other activities and not ableto attend to the ECG monitor. The EMT could, alternatively select amonitoring function, which (i) sounds an audible alarm if a heart rateor rhythm abnormality is detected by the PU, but (ii) does not rendertreatment, allowing EMT performance of the latter. Yet another EMTalternative via the modified Communications and Triage Screen is ahybrid of the two previously mentioned approaches. That is, the AED/Pcould be set up to (i) sound an audible alarm if a heart rate or rhythmabnormality is detected by the PU, and (ii) delay treatment for aprogrammable number of seconds, such that the AED/P gives the EMT acertain amount of time to render treatment, before the AED/P does.

c) The EMT may attempt to restore communications by plugging telephonecable 176 (see Section 2.2 and FIG. 7A), extending from the PU attachedto the victim, into a nearby telephone jack of the public telephonenetwork, if available, at the arrest scene. The EMT would then attemptto re-establish communication with the MP via the public telephonenetwork. This attempt would be initiated by simply pressing emergencybutton 106 on the portable unit (FIG. 6A).

d) The EMT may attempt to restore communications by plugging telephonecable 176, extending from the PU attached to the victim, into the femaletelephone jack 155 of the stationary unit, if he is within reach of it.The EMT would then attempt to re-establish communications with the MPvia the SU by pressing emergency button 106 on the PU.

e) The EMT may manipulate PU antenna 162 by either (i) extending orretracting it and/or (ii) changing its orientation; followed in eithercase by pressing emergency button 106 on the PU.

4.5.7.5.2 EMT Communications Choices Using a Second Portable Unit

The EMT, if he has brought a PU to the arrest scene, may attempt tocontact the MP via the PU not currently attached to the victim,hereinafter referred to as “PU-2” (whether it be the new or the oldone). Certain actions by the EMT may render the second PU more likely tocommunicate with the MP, than is the PU which is attached to the victim,hereinafter referred to as “PU-1.” These actions include:

a) moving PU-2 outside or nearer to the outside of a building;

b) moving PU-2 so that it is within reach of a telephone jack whichallows connection to the public telephone network;

c) moving PU-2 so that it is located in between the stationary unit andPU-1; and

d) moving PU-2 to any other location.

There are two possible approaches to using PU-2: a) using PU-2 as theonly PU; and b) using both PU-1 and PU-2 in tandem.

4.5.7.5.2.1 Choice in which PU-2 is the Only PU which Communicates withthe Central Station

The rationale for using PU-2 as the only PU, instead of PU-1 is becausePU-2 might be capable of communication with the CS even though PU-1 isnot. Possible reasons for non-equivalent performance of the PUs are: a)PU-2 being a different model portable unit (though nevertheless anembodiment of the invention) with a more robust communications system;b) PU-2 being in a different position, allowing for greater signalstrength (in either or both directions) than PU-1; or c) a malfunctionin PU-1.

If PU-2 is successful in communicating with the central station, methodsof using it include: a) simply using it as a communication devicebetween MP and EMT, without PU-2 having a direct link to the victim; b)connecting PU-2 to the victim's electrode pad by switching the universalconnectors (analogous to the procedure described in Section 4.5.7.2.2);or c) connecting PU-2 to PU-1 by extending the telephone cable 176coming from PU-1, to PU-2, resulting in tandem operation of the PUs.(There are also other possible means of linking PU-2 to PU-1, seebelow.)

4.5.7.5.2.2 Choices in which Both PU-1 and PU-2 are Used in Tandem; EvenMore Elaborate Links

There are multiple possible configurations using both PUs in tandemoperation. The features of the link that may be varied include:

a) The first segment of the link, i.e. that from PU-1 to PU-2, may bewireless or wire. The terms “wireless” and “wire” have been definedabove, in Section 4.1.2.4. In a preferred embodiment of the invention,the wire may be cable 176 coming from PU-1 which may be plugged intofemale jack 153 of PU-2.

b) The second segment of the link, i.e. that from PU 2 towards thecentral station, may connect PU-2 with either (i) the stationary unit or(ii) the central station.

c) If the second segment of the link is between PU-2 and the SU, it maybe wireless or wire. If it is a wire link, it may be achieved byplugging telephone cable 176, extending from the PU-2, into the femaletelephone jack 155 of the stationary unit.

d) If the second segment of the link is between PU-2 and the centralstation, it may be wireless or wire. If it is a wire link, it may beachieved by plugging telephone cable 176, extending from PU-2, into afemale telephone jack of the public telephone network.

Table 13, below, lists different possible combinations of theaforementioned first segment and second segment choices.

TABLE 13 Communication Choices Using the Second PU as a Relay Segment #1Segment #2 Choice PU-1 to PU-2 PU-2 to SU PU-2 to CS 1A WirelessWireless 1B Wireless Wireless 2A Wireless Wire to TELCO 2B Wireless Wireto SU 3A Wire Wireless 3B Wire Wireless 4A Wire Wire to TELCO 4B WireWire to SU

Even more elaborate links involving larger numbers of PUs in tandem arepossible.

Replacement of a PU at the SU is more complex when the link between theMP and the EMT or victim consists of two PUs. If a third PU isavailable, it may be attached to the SU. If not there may be a periodwithout communication between the MP and the EMT or victim, during whichtime one of the PUs is moved to the SU and attached to it (as describedin Section 4.5.7.4, above).

4.5.7.6. Possible Need for Two Nearly Simultaneous MP ConversationsDuring Phase Seven

During the first four phases of the sample arrest, there are a number oftimes when the MP may be called upon to perform multiple taskssimultaneously (see Section 4.4.6). During these phases, however, thereis virtually no instance when the MP must speak to two individualssimultaneously. (Even when MP calls the emergency medical team local tothe victim, MP need not interrupt his conversation with the enabler [seeSection 4.5.3.1].)

Since phase seven involves both MP guidance of the EMT and MP guidanceof the person replacing the PU, it is possible that, under circumstanceswhen two PUs are present at the arrest scene, the MP would be calledupon to conduct separate but simultaneous conversations with each of theEMT and the enabler. However, this need for coincidental action isexpected to be easily remediable since:

a) It is always possible to delay PU housekeeping and replacement;

b) PU housekeeping and replacement consists of multiple sub-tasks;therefore, the MP could interweave his supervision of one or more ofthese sub-tasks with his supervision of the EMT;

c) The EMT is expected to be capable of a certain substantial level ofexpertise and competence so that MP should be able to break away fromconversation with the EMT for brief periods of time; and

d) The MP has the ability to assign excess workload immediately byaccessing the Master Triage Screen (FIG. 42) from the Screen Menu (FIG.43). The Master Triage Screen (discussed below) allows the MP to observethe activity of other MPs and hand off work to one or more of them, asneeded.

4.5.7.7 The Circumstance in which EMT Does Not Bring a Replacement PU

If the EMT does not bring a second PU, then either: a) at some pointprior to leaving the scene of the arrest, he must detach the PU from thevictim (option three); or b) the PU remains attached to the victim andboth are transported to the hospital (option four).

4.5.7.7.1 Option Three: Sole PU Remains at the Arrest Scene

If EMT is to leave the PU at the arrest scene, the MP requests thateither the enabler or the EMT perform the housekeeping functionsdiscussed in Section 4.5.7.3, and then return the PU to the SU (as perSection 4.5.7.4). In this circumstance, the EMT would maximally benefitfrom the expertise of the MP by delaying PU detachment as long as ispractical.

4.5.7.7.2 Option Four: Sole PU is to be Transported with the Victim

If the PU is to be transported with the victim to the hospital, areplacement PU must be supplied to the arrest scene. This circumstanceis referred to and discussed below in Sections 4.5.7.8.2 and 4.6.1.

4.5.7.8 Protocol Endpoints During Phase Seven

Phase seven ends when both: a) the victim is no longer attached to thePU; and b) a PU has been attached to the SU.

4.5.7.8.1 Definition of Victim Detachment from PU

The victim is no longer attached to the PU if:

a) the victim is disconnected from PU after arriving in the hospital;

b) the victim regains consciousness during the arrest, and insists onbeing disconnected from the PU, and leaving under his own power;

c) the EMT brings a non-PU defibrillator to the arrest, disconnects thePU from the victim, and leaves the PU at the arrest scene; or

d) the victim, after all appropriate medical and statutoryconsideration, is no longer considered to be a candidate for furthertherapeutic efforts, and is disconnected from the PU (see Sections4.3.1.4 (h), 4.5.3.2 (b), and 4.5.5.2 (i)).

Furthermore, if, after assuming control of the PU, EMT (or physicians)wish no MP involvement, then the victim-related interaction with thesystem according to the invention may effectively end.

4.5.7.8.2 Circumstances in which a PU Would Not Be Promptly Replaced

4.5.7.8.2.1 PU Non-Replacement at the Arrest Site

Ordinarily, a PU is reattached to the SU. This will occur if: a) the EMTbrings a new PU and the new PU is attached to the SU (option one;described in Section 4.5.7.2.1); b) the EMT brings a new PU, the new PUis attached to the victim, and the old PU is attached to the SU (optiontwo; described in Section 4.5.7.2.2); or c) the EMT does not bring a newPU, the old PU is left at the arrest scene, and is reattached to the SU(option three; described in Section 4.5.7.7.1).

The circumstances under which reattachment of a PU to the SU would notoccur are: a) although the EMT brings a new PU, no one attaches it tothe SU; or b) the EMT does not bring a new PU and takes the old PU(attached to the victim) to the hospital (option four; 4.5.7.7.2). Ineither of these two circumstances, a person responsible for maintainingthe portable units (see Section 4.6.1) will have to be dispatched to thescene, to ensure PU replacement.

4.5.7.8.2.2 Non-Replacement of the EMT PU

The PU which EMT brought to the hospital may be left there (see Section4.1.8). If so, either EMT must later retrieve and restock it, or aperson responsible for maintaining the portable units (see Section4.6.1) will have to be dispatched to the hospital to retrieve it.

4.6 Post-Arrest Issues

Two types of PU and SU maintenance procedures assure that the equipmentis ready and optimized for future use. These procedures: a) confirm thatthe PU is properly stocked and prepared for subsequent events; and b)confirm the proper functioning and integrity (both physical andoperational) of the PU and SU; and c) replace or update PU hardware orsoftware as needed.

4.6.1 On-Site Equipment Inspection and Assessment

The first type of maintenance procedure involves periodic on-site visitsto each PU or PU/SU combination by a person whose duty it is to inspect,assess, repair, update and/or replace portable and stationary units.This person may be: a) from, or related to the same organization thatincludes the central station and/or the medical professional; or b) fromanother organization whose function is to maintain portable andstationary units.

4.6.1.1 Timing of the On-Site Visit

An on-site visit must occur:

a) if neither enabler, EMT or any other person reattached a PU to theSU, at the arrest scene, at the time of previous PU use;

b) if EMT is no longer has a PU, having previously had one (see Section4.5.7.8.2.2, above);

c) if a PU has been damaged as a result of vandalization, or has beenstolen;

d) if the amount of any disposable items in a PU (spare versions ofwhich are kept in the PU tool-kit) has fallen below an acceptablenumber;

e) if any non-disposable item (e.g. wireless headset) ordinarily kept ina PU tool-kit is found to be missing;

f) if, during a remote equipment assessment and inspection (see Section4.6.2, below), a PU and/or SU malfunction is detected which can not beremedied from a remote location; or

g) if a hardware update or replacement is required.

An on-site visit may occur:

a) after any use of a portable unit;

b) if there is a question of attempted vandalization of, or tamperingwith a PU, even though it functions properly during a remote inspectionand assessment;

c) in order to replace or update software; or

d) on a periodic basis, even if a PU and SU show no definitive signs ofneeding direct attention.

4.6.1.2 Items Assessed During the On-Site Evaluation Process

The duties of this person performing this inspection and assessmentinclude (but are not limited to):

a) performing any post-arrest housekeeping functions which were notdone, were not completed, or were not done properly, at the time whenenabler (or other designated person) was requested to perform them;

b) restocking any necessary disposable items (such as electrode pad(s))which may have been used during the last event(s);

c) restocking any non-disposable items (such as scissors 170, headset168) which may not have been properly replaced at the time of the lastuse;

d) replacing one or more rechargeable PU and or SU batteries (seebelow), if necessary;

e) inspecting and assessing areas and parts of the system which are noteasily assessed by the video camera including but not limited to:

-   -   (i) cables 212A, 212B, 214, 216, 217, 222, 224, 226, 228 and 229        which link already hooked up electrode pads within the PU        tool-kit (FIG. 7B);    -   (ii) universal connectors 218A-E and 220A-E, checking for damage        or pin misalignment;    -   (iii) telephone cable 176 within the PU tool-kit (FIG. 7A);    -   (iv) oximetry sensor 174 and the cable which links it to the PU        (FIG. 7A);    -   (v) blood pressure apparatus 172 and its link to the PU;    -   (vi) headset 168;    -   (vii) connectors 186, 188 on the rear surface of the PU and the        front surface of the SU 190, 192;    -   (viii) PU antenna 162 and and SU antenna 164, making sure        neither is bent or broken, and that the motorized deployment        mechanism, if any, is sound;    -   (ix) video camera 154 (FIG. 6A) and its extensible boom 112        (FIG. 6 b); and    -   (x) SU locking projection 194 (FIG. 9) and the PU-SU lock and        its associated sensors;

f) inspecting and assessing the SU connection with the public telephonenetwork;

g) inspecting and assessing the SU power connection;

h) cleaning and/or disinfecting any part of the system which may requiresuch procedure; and

i) replacing a PU, SU, or both, if (i) it cannot be properly made readyfor future use, or (ii) a newer, improved version of it has becomeavailable (see Section 4.6.3, below). The replacement may involve anentire unit or one or more parts, circuit boards or components of theunit(s).

4.6.2 Remote Equipment Inspection and Assessment

The second type of maintenance procedure involves the confirmation ofproper PU and SU functioning by performing periodic remote diagnosticevaluation of both the PU and the SU. The evaluation may occur over anyor all of the communications modalities which link: a) the PU/SU; and b)the CS or another diagnostic facility (see Section 4.6.2.1). The personperforming the inspection and assessment may be the MP or anothertechnically qualified person. In order to perform this process, acommand is sent to the PU which causes the master control unit 130 toenter master control state 4 (see Table 1 and Section 1.3.1.2 andbelow). FIGS. 55A and 55B (discussed below) show the flow diagramsrelated to such diagnostic checking. FIG. 41 (discussed below) shows thescreen menu which allows the person performing the inspection to do so.

4.6.2.1 Timing of the Remote Evaluation Process

A remote inspection and assessment:

a) occurs after the PU has been used, as soon as a replacement PU isattached to the SU (see Section 4.5.7.4.4).;

b) may be periodically initiated from the outside by (i) the centralstation or (ii) another diagnostic facility with equipment similar tothat of the central station but not necessarily staffed by medicalprofessionals;

c) may be periodically initiated by the PU (see below), on a routinebasis; and

d) may be initiated by the PU at non-routine times, if it detects afault (e.g. low voltage).

4.6.2.2 Items Assessed During the Remote Evaluation Process

This inspection and assessment includes but is not limited to:

a) the PU battery;

b) the SU battery;

c) the position of all PU sensor switches;

d) all connectors;

e) high voltage circuitry within the PU;

f) the electrode pads;

g) blood pressure and oxygen saturation sensors;

h) the connection with the public telephone network;

i) the PU transmitters and receivers;

j) the SU transmitters and receivers;

k) the PU external audio and video elements;

l) the wireless headset;

m) the PU global positioning system; and

n) clocks within the PU/SU.

In addition, the PU can be used to inspect itself by using the videocamera 154. This can be done by (i) extending the video boom 112, and(ii) having it turn back on itself, thus causing it to become U-shaped,and thereby allow the camera to look back at the PU. This same techniquecan be used to determine if the PU screens 156 are performing properly.An alternative technique for visualizing the PU and its screens wouldinvolve a mirror placed on a wall opposite the PU. The video cameracould be pointed at the mirror to allow PU/SU inspection and assessment.

4.6.3 PU and SU Hardware and Software Updates

From time to time, improved versions of the PU hardware or software maybecome available.

Hardware may be replaced at the time of an on-site visit. Hardwarereplacement may include: a) individual PU or SU parts, circuit boards,or components; or b) the entire PU or SU. Hardware may be replacedbecause of: a) a malfunctioning part, circuit board, component or unit;or b) the desire to replace a part, circuit board, component or unitwith one which is newer or has improved features.

Software may be replaced or updated (i) during a PU on-site visit, or(ii) remotely, by downloading it from the central station via any of thecommunication modalities available between the CS and the PU/SU (seebelow).

TABLE 14 Flow Diagrams of Events During a Cardiac Arrest Event FIG. 1)Communications handshake, PU component 12 2) Communications handshake,CS component 13 3) Data/Commands handshake between 14 portable unit andcentral station 4) Audio handshake between enabler and 15 medicalprofessional 4) Informational handshake between 16A enabler and medicalprofessional 5) PU-SU Lock Release 16B-C 6) Enabler transports portableunit to victim 17 7) Medical professional directs enabler 18 in portableunit setup 8) Medical professional assesses rhythm 19 9) Medicalprofessional administers 20-23 defibrillation and pacing, as needed 10) Confirmation and Error Signals 24

TABLE 15 Central Station Screen Summary FIG. Screen Content 25Communication Status and Triage 26 Voice Prompts 27 Portable UnitDeployment 28 Video Control and Instruction 29 Initial ECG 30 ElectrodeMatrix Pad Setup 31 Five Electrode Pad Setup 32 Multiple SingleElectrode Pad Setup 33 Main Defibrillation 34 Defibrillation Energy 35Synchronization 36 Pulse Contour 37 Antitachycardia Pacing Parameters 38Main Pacing 39 Pacing Amplitude 40 Bradycardia Pacing Rate 41MP-Directed Portable Unit Check and Maintenance 42 Master Triage 43 MainScreen Menu 44 Command Confirmation and Event Log

TABLE 16 Signals During Communication (Layer #1) Handshake Sent byPortable Unit: Sent by Central Station: PU-1 Button Press CS-1 ButtonPress Received PU-2 Intact Handshake CS-2 Intact Handshake PU-3 CS-4Received CS-3 PU-4 Received PU-4 No CS Signal Received CS-4 No PU SignalReceived PU-5A Pseudo-Button Press: CS-5 Pseudo Button Press FaultDetected During Received PU-initiated Daily Self-Diagnostic Check PU-5BPseudo-Button Press: PU Call to CS for Routine Monthly Self-DiagnosticCheck PU-6 Pseudo-Button Press: CS-6 Diagnostic Check CS-6 ReceivedInitiated by CS Note: The format in this table applies to direct PU-CShandshakes. An analogous format may be used for a PU-SU handshake, for aSU-CS handshake, or for a handshake between any two units in which acommunication handshake is attempted.

TABLE 17 Testing During Data/Commands (Layer #2) Handshake COMPONENT: 1A1B 2 3A 3B 4 5 4B 6A 6B 7 8A 8B Confirmation #1 X X Confirmation #2 X XX X Confirmation #3 X X X X X X X X Confirmation #4 X X X X X X X X X XTest Signal X X X X X MP Receiving Voice X X X X X X Prompt = MP (VP)Key 1A = CS Audio Input 1B = CS Transmitter 2 = CS to PU Routing 3A = PUReceiver 3B = PU Audio Output 4A = Enabler Hearing 4 = EnablerCooperation 4B = Enabler Speaking 6A = PU Audio Input 6B = PUTransmitter 7 = PU to CS Routing 8A = CS Receiver 8B = CS Audio Output X= Explicit Testing of Component

TABLE 18 Testing During Audio (Layer #3) Handshake COMPONENT: 1A 1B 2 3A3B 4A 4 4B 6A 6B 7 8A 8B MP Hearing X X X X X X X EN = MP (EN) ENHearing Voice X X i i i i i i I Prompt = EN (VP) EN Hearing X X X X X Xi i i i i i i MP = EN (MP) Key 1A = CS Audio Input 1B = CS Transmitter 2= CS to PU Routing 3A = PU Receiver 3B = PU Audio Output 4 = EnablerHearing 5 = Enabler Speaking 6A = PU Audio Input 6B = PU Transmitter 7 =PU to CS Routing 8A = CS Receiver 8B = CS Audio Output X = ExplicitTesting of Component i = Implicit Testing of Component Note: It is alsopossible to test the stationary unit transmitters and receivers duringthe audio handshake. Such testing is not explicitly addressed in thistable.

TABLE 19 Testing During Enabler-MP Handshake: Which Tests are Abnormalfor Each Component Failure MP MP MP EN EN TEST: VSE SE LE VLE (AB) (VP)(EN) (VP) (MP) 1A fails − − − − + + + + − 1B fails + − − − + + + + − 2fails + + − − + + + + − 3A fails + + − − + + + + − 3B fails + + + − +− + − − 4A fails + + + + + + +/− − − 4 fails + + + + + + +/− − − 4Bfails + + + + + + − + + 6A fails + + + − − − −  +*  +* 6B fails + + − −− − −  +*  +* 7 fails + + − − − − −  +*  +* 8A fails + − − − − − −  +* +* 8B fails − − − − − − −  +*  +* Key + All components evaluated bythis test: properly functioning. − One or more components evaluated bythis test: not properly functioning. +/− Test result may be positive ornegative. +* Enabler hears MP or VP, but MP is not aware of this. 1A =CS Audio Input 1B = CS Transmitter 2 = CS to PU Routing 3A = PU Receiver3B = PU Audio Output 4 = Enabler Hearing 5 = Enabler Speaking 6A = PUAudio Input 6B = PU Transmitter 7 = PU to CS Routing 8A = CS Receiver 8B= CS Audio Output X = Explicit Testing of Component i = Implicit Testingof Component Note: It is also possible to test the stationary unittransmitters and recievers during the audio handshake. Such testing isnot explicitly addressed in this table.

TABLE 20 Options for Communications Enhancement During the FourHandshakes of the Enabler-MP Link Options 1-3: Modifications in theCS-to-PU Arm Options 1a: Changes in CS processing input Options 1bChanges in CS communications output Options 2: Changes in CS-to-PUrouting at Central Station or at Stationary Unit Options 3a: Changes inPU communications input Options 3b: Changes in PU processing outputOptions 4-5: Modifications in the PU-to-Enabler and in the Enabler-to-PUArms Option 4a: Ask Enabler to use headset Options 4b: In the event of anon-English speaking Enabler, Medical Professional options include: i)Hand off the conversation to a foreign language speaking medicalprofessional who restarts the protocol, or ii) Use foreign languagevoice prompts Option 5a: Ask Enabler to speak louder and/or to moredirectly face the PU while speaking Option 5b: Use speech recognitiontechnology Options 6-8: Modifications in the PU-to-CS Arm Options 6a:Changes in PU processing input Options 6b: Changes in PU communicationsoutput Options 7: Changes in PU-to-CS routing at Portable Unit or atStationary Unit Options 8a: Changes in CS communications input Options8b: Changes in CS processing output Option 9: Other Central StationAlternative Option 9: In the event of a suspected mischievous act,Medical Professional calls police or security local to the PortableUnit. (Further assessment may be based on observations made with thevideo camera within the Portable Unit.) Note: It is also possible tomodify the CS-to-PU arm and the PU-to-CS arm by making changes in thestationary unit transmitters and receivers. These possibilities are notaddressed in this table.

5. Flow Diagrams 5.1 Communications Handshake 5.1.1 Overview

In order to remotely manage the highly critical situation of a cardiacarrest in a safe manner, a situation must be created that is as close aspossible to the remote MP being present at the emergency scene. A highlyrobust communication system, which reacts quickly and efficiently tofailures, potential failures or degradation of “fidelity” is mandatory.A series of backup systems must be available. In order for these backupsystems to work with maximal efficiency, the need for their functionmust be instantly recognized.

Remote resuscitation is made practical by AED backup, as discussedpreviously, and by a system which reacts instantly to a communicationsinterruption by bringing this backup system on line. To accomplish nearinstantaneous recognition of communications interruption, a constantlyrepeating handshaking process between the CS and the PU occurs duringsystem operation. At the first sign of communications interruption, theAED is brought on-line, and it continues to function as the “director”of the resuscitation until satisfactory communication between the CS andthe PU is re-established.

The flow diagrams describe a multilayer handshaking process. Thecommunications handshake perpetually reconfirms the existence of anintact communications link between the CS and the PU. The data/commandshandshake (FIG. 14) is performed once after the completion of theinitial communications handshake; It is repeated if the communicationshandshake is interrupted and is effectively repeated with thetransmission and execution of each command by the MP, as evidenced bythe cascade of confirmation signals which follow each command. The audiohandshake is performed formally once per event, but is, in principlecontinuously updated whenever conversation between the MP and theenabler (or EMT) takes place.

FIGS. 12A, 12B and 12C show the flow diagram for the PU component of thecommunications handshake during system operation; FIG. 13A shows the CScomponent. FIGS. 12D, 12E and 12F show the flow diagram for the PUcomponent of the communications handshake during diagnostic evaluation;FIG. 13B shows the CS component. Table 16 shows the definitions of eachof the eight communications handshaking signals, and additional signalsduring diagnostic testing. Table 20 gives additional information about“options” referred to in these figures. Tables 17, 18 and 19 alsocontain relevant information.

In general, the handshake sections hereinbelow do not address the SUcomponent. Doing so would add much complexity to the discussion, withoutcontributing to the substance of it. The SU is discussed specificallyabove, and is addressed again in Section 7.

5.1.2 Communications Handshake, PU Component

Following “button press”, i.e. depression of the PU activation button106 by a potential enabler, block 375, (FIG. 12A) leads to the zeroing376A of all counters, the powering up 376B of hibernating circuits, theinitiation 376C of a self checking routine (which may include all orpart of the diagnostic check depicted in FIG. 55), the activation 376Dof the PU video camera and the initiation, 376E of a ten second delayduring which interval the completion of a proper communicationshandshake and a data/commands handshake must occur or AED function isactivated.

Block 375 also leads to block 377, the transmission by the PU of aninitiating handshaking signal designated PU-1 and indicating buttonpress (see Table 16). When the CS receives PU-1 it sends CS-1 (ButtonPress Received). When CS-1 is received by the PU, block 379, the PUtransmits PU-2 (Intact Handshake, PU Side), block 389.

The CS will, in response to PU-2, transmit CS-2 (Intact Handshake, CSSide). The PU will, in response to CS-2, transmit PU-2. This continuousexchange of PU-2 and CS-2 signals constitutes an intact communicationshandshake between the PU and the CS.

If, at block 379, CS-1 is not received, block 384 checks if counter A₁is even. Since at block 377 all counters were increased by 1, it is oddthe first time through, resulting in no change in communicationparameters, and therefore resulting in a repeat transmission of PU-1using the same communication parameters as for the first PU-1transmission.

If CS-1 is not received following a second PU-1 transmission, (whichresults in an increase in A₁ to the value 2) block 379 leads to 384which leads to 385, communications options 6B, 7 (see Table 20). Thesystem makes an alteration in PU communications output (option 6B) orrouting (option 7), returning to block 377 and another transmission ofPU-1.

As long as the handshake fails to occur, one of options 6B or 7 will bechanged with every other transmission of PU-1. Because it is possiblethat the CS is responding and the PU is not receiving the response,block 386 will, with every fourth attempt at communication with the CS,exercise one of options 3A, block 387A, changing the PU communicationsinput characteristics.

If the eighth transmission of PU-1 is not followed by a response fromthe CS, block 380, the backup plan is invoked which includes:

a) block 381A, the setting of MC=2, enabling AED function;

b) block 381B, the calling of local 9-1-1, pre-programmed into thedevice;

c) block 381C, the issuance of an AED introductory message; and

d) the release of the PU-SU lock, with block 381D leading to block 383B.

The same four events occur if, block 382, the data/commands handshake isnot completed within 10 seconds.

There are two ways in which an already established loop of continuouslyrepeating transmitted PU-2 and received CS-2 signals may be interrupted.The first is if the CS fails to detect a PU signal and transmits CS-4(No PU Signal Received by the CS). The second is if the PU does notreceive any CS signal. Therefore the “Intact Handshake Loop” consists ofa continuously repeating sequence of:

a) block 389 (PU-2 transmission);

b) block 390 with a negative response (i.e. no CS-4 signal received bythe PU); and

c) block 391 with a positive response (i.e. CS-2 received).

If CS-2 is not received, the protocol leads to block 393B, block U 393A(FIG. 12B). This results in a) the issuance of voice prompt 396B shownin the figure, which informs the enabler of upcoming AED control, and b)setting MC=2, block 396A. The latter leads to a loop of continuouslyrepeating events which will occur as long as the PU does not receive asCS signal of any kind. The loop consists of:

a) the transmission by the PU of PU-4 (No CS Signal Received), block397;

b) an increase in counter C₁ by 1, block 398;

c) a check of the value of this counter, block 399. If the value is amultiple of four, then, block 400, one of options 3A (modify PUcommunications input) occurs;

d) Whether or not it is a multiple of four, block 401, checks if CS-3has been received by the PU (which would indicate the last PUtransmission, PU-4, was received by the CS). (i) If yes, the fact thatthe CS has responded to a PU handshake signal (PU-4) and that the PU hasreceived a CS signal (CS-3) indicates the restoration of two-waycommunication. Accordingly, blocks 402B and 402A, counters are reset andthe PU event memory is transmitted to the CS, so that the MP may learnwhat has transpired during the communications interruption. Then block388B leads to block V 388A (FIG. 12), returning to the “Intact HandshakeLoop”. (ii) If CS-3 was not received, block 403 checks if CS-4 wasreceived. If no, block 397 is a retransmission of PU-4 and the beginningof another passage around the “Portable Unit Can't Hear CS Loop.” Everyfourth time around this loop, counter C₁ will be a multiple of four,resulting in a change in options 3A. If, at block 403, CS-4 was receivedby the PU, indicating that the CS has not received a PU handshakesignal, block 405B leads to FIG. 12C, indicating a different set ofincomplete handshake conditions: i.e. that the PU is now receivinghandshake signals and the CS is not. This condition—CS-4 received by thePU—can also occur during the “Intact Handshake Loop” of FIG. 12A, ifblock 390 indicates that CS-4 has been received by the PU, leading toblock 392B, to block Z 392A, FIG. 12C.

The events that follow parallel but are not identical to those depictedin FIG. 12B. The loop which indicates that the CS is not detecting PUhandshake signals, but that the PU is detecting CS signals (implicit inthe PU receipt of CS-4) consists of blocks 409 (at which thetransmission of PU-3 indicates that the PU has received CS-4), 410, 411,413 and 415. The AED message 408B and the setting of MC=2, block 408A,occur if the loop is entered from block Z 392A but not from block W405A, because in the former case, it marks the end of an intacthandshake; In the latter case it marks the perpetuation of a conditionof inadequate communication. Counter D₁ changes every other time throughthe loop. When its value is even, block 412 results in one ofcommunication options 6B or 7 (discussed above). The loop is exited byone of two events:

a) If CS-2 is received, block 413 leads to blocks 414A (download andtransmit memory to CS), 414B (reset counters) and 388C (return to“Intact Handshake Loop”).

b) If neither CS-2 nor CS-4 is received, block 415 leads to block 404B,to block S 404A and a return to the aforementioned “PU Can't Hear CSLoop” of FIG. 12B.

At all times, one of the aforementioned three loops will be in progress.It is possible that conditions in which certain signals are at themargin of acceptability, and hence are at times classified as present,and at other times as absent, will result in “hunting”, i.e.continuously shifting from one loop to another. An anti-huntingalgorithm could easily stabilize the condition; such an algorithm woulddecrease the frequency of transitions from one loop to another, e.g. byrequiring multiple consecutive similar results before making atransition from one loop to another.

Implicit in the handshaking process is that the timing of PU and of CShandshaking signals correspond. This is easily accomplished by meansknown in the art.

The values for which the counter change receiving or transmissioncharacteristics are, to a certain extent arbitrary, as is the delayuntil AED function is begun.

5.1.3 Communications Handshake, CS Component

FIG. 13A shows the CS events during the communications handshake. Uponreceipt of PU-1, block 466, the MP is notified block 467 and the CSsends handshake signal CS-1 (PU-1 Received), block 468. The CS thenwaits for PU-2, which would indicate that the PU has received CS-1. Thisindicates an intact communications handshake in that the CS has detectedthe PU signals (PU-1 and PU-2) and can infer that the PU has detectedthe CS signal (since PU-2 implies that CS-1 was received by the PU).This initiates the “Intact Handshake Loop”. If, however, PU-2 was notreceived, block 469 leads to block 470 and options 1B (change in CScommunications output) and/or 2 (change in CS routing).

The “Intact Handshake Loop” at the CS consists of blocks 471, followedby

a) block 471 (CS-2 transmission);

b) block 472 with a negative response (i.e. no PU-4 signal received bythe CS); and

c) block 473 with a positive response (i.e. PU-2 received). If PU-2 isnot received, the protocol leads to block 477 and a loop which indicatesthat the CS cannot hear the PU, consisting of blocks 477, 478, 479 and480. Each time 477 is reached one or more of options 8A (CScommunications input) is modified. Each time 478 is reached, a CS-4signal is sent (indicating that PU signal has not been received). Thereare two possible exits from the loop:

a) If PU-3 is received, indicating that the PU has received the CS-4signal, and, since the CS is receiving the PU-3 signal, thereforeindicating that each is capable of detecting the other. This results ina return to the “Intact Handshake Loop”.

b) If PU-4 is received, it indicates a change in status to anotherunsatisfactory handshaking state. At such a juncture, the CS is now inreceipt of PU signals, but the signal, PU-4, indicates that the PU isnot in receipt of CS signals. This leads to a loop involving blocks 472,475 and 476. Each transit through the loop results in a modification ofeither CS communications output (option 1B) or routing (option 2). Eachtransit results in the retransmission of CS-3, attempting to let the PUknow that the PU-4 signal last sent was received. Exit from the loopoccurs when a PU-4 signal is not received, and can lead to either areturn to the intact handshake loop (if PU-2 is next received, block473), or to the “CS Can't Hear PU Loop” (if PU-2 is not next received,block 473).

After the completion of an adequate communications handshake, whetherfor the first time during an emergency event, or following the sequenceof a) intact communications handshake, b) interruption in communicationshandshake and c) restoration of communications handshake, thedata/commands handshake must be established before the audio andinformational handshakes. Accordingly, if block 471 was reached after aninitial communications handshake or a restored one, block 481 leads toblock 474B and initiation (or re-initiation) of the data/commandshandshake (see FIG. 14N).

5.1.4 Handshakes During Diagnostic Checking

If, during a periodic self checking routine, the PU discovers a fault(see FIG. 55) it attempts to contact the CS by initiating a“Pseudo-Button Press.” This event is initiated when fault detectionleads to block □ 418A, which leads to the sending of handshake signalPU-5A, (Table 16) analogous in action to PU-1. The routine which followsthe Pseudo-Button Press is very closely analogous to an actual buttonpress and, as such, FIG. 12D is analogous to 12A, FIG. 12E is analogousto 12B, FIG. 12F is analogous to 12C and FIG. 13B is analogous to 13A.

The other events which can initiate a Pseudo-Button Press include:

a) the monthly routine for transmitting the results of daily PU-SU selfchecks to the CS, wherein block 419 leads to block 423 and thetransmission of handshake signal PU-5B; and

b) the receipt by the PU of signal CS-6, block 420, indicating adiagnostic check initiated by the CS, and resulting in the transmissionof PU-6 (indicating that the PU has received CS-6).

The events which follow the initial signal transmission by the PU afterthe Pseudo-Button Press parallel those after a real Button Press:

a) Receipt of CS-5 (block 425) is analogous to receipt of CS-1 by thePU;

b) The “Intact Handshake Loop” (blocks 436, 437 and 438 continuouslyrepeating) during the diagnostic check consists of the identicalsequence of events as those during ordinary system operation;

c) The exit from the “Intact Handshake Loop” in the event that CS-2 isnot received leads to block U□ 440B and the “Portable Unit Can't Hear CSLoop” of FIG. 12E. The only difference between FIG. 12E and 12B is thatthe enabler voice prompt and the MC=2 setting are herein replaced by theactivation of a PU alarm, block 444, upon entering the loop, and itsdeactivation, block 450, upon leaving the loop.

d) The exit from the “Intact Handshake Loop” in the event that CS-4 isreceived leads to block Z□ 439B and the “Portable Unit Can Hear CS, ButCS Can't Hear Portable Unit Loop” of FIG. 12F. The only differencebetween FIG. 12F and 12C is that the enabler voice prompt and the MC=2setting are replaced by the activation of the PU alarm, block 456, uponentering the loop, and its deactivation, block 462, upon leaving theloop.

There is no need for backup AED function, since there is no victim, andhence the elements corresponding to AED backup do not have a parallel inFIG. 12D, except for the activation of the PU alarm, block 427, after 24attempts (block 426) to establish a handshake.

The flow diagram for the CS component of the diagnostic handshakediffers from the regular handshake of FIG. 13A only in that the formerhas two “Initiate Handshake Loops”, since both the CS and the PU caninitiate this communication.

5.2 The Data/Commands Handshake

FIG. 14A introduces a representation of the invention which facilitatessome of the analysis and discussion of its operations. It shows the flowof information such as a command (in a general sense) from the MPthrough the CS, through a CS-to-PU communications link, through the PUto either the enabler (giving him instructions), the victim (e.g.delivering a shock) or the EMT (e.g. asking him to identify himself).This flow is followed by a return flow of information, toward the MP. Inthe case of the enabler, it may be his description of the victim. In thecase of the victim, it may be his ECG signals. In the case of the MP, itmay be his identifying information. The information then enters the PU,passes through a PU-to-CS communications link, then through the CS andon to the MP.

Each of the twelve components of this sequence has been given analphanumeric designation, listed in the upper left corner of each box,and corresponding to the options listed in Table 20, and also referredto in Tables 17-19.

Thus the full summary of information flow from the MP consists of thefollowing sequence:

1A) the CS Processing Input 506,

1B) the CS Communications Output 508,

2) the CS-to-PU Communications Link 510,

3A) the PU Communications Input 512,

3B) the PU Processing Output 514,

4) the Input to the Enabler, Victim or EMT 516,

5) the Output from the Enabler, Victim or EMT 517,

6A) the PU Processing Input 519,

6B) the PU Communications Output 521,

7) the PU-to-CS Communications Link 523,

8A) the CS Communications Input 525,

8B) the CS Processing Output 527.

FIG. 14B shows the communications handshake, consisting of a continuouswave of signaling involving the core components of the system: elements508, 510, 512, path 532 (which lies within the PU), 521, 523, 525 and531 (lying within the CS).

FIG. 14C shows the crux of the data/commands handshake. In order to showthat the system is functional beyond the core components evaluated bythe communications handshake, a command is sent from the MP to the CSProcessing Unit 506, and on to 508, 510, 512, 514, path 534, 519, 521,523, 525 and 527. Path 523 may lie within the PU or extend outside ofit. An example of a command which would serve this purpose and remaininside the system would be a command for the PU Processing Unit 519 toissue a internal test signal for transmission to the CS as a datasignal. This is shown schematically in FIG. 14I, where test signal 535is produced and passed along to the CS Processing Output. An example ofa command which would extend outside of the PU would be the productionof a sound by the PU speaker, which is then inputted through the PUmicrophone. The result of such testing is a demonstration that thecomponents outside of the core are intact, and that the system is readyfor operation.

Confirmation signals are used to locate a fault if the data/commandshandshake fails (see below). In the event that the command depicted inFIG. 14C does not result in a return signal to the MP, the system canassessed in smaller steps, such that a fault is easier to pinpoint.

FIG. 14D shows confirmation signal #1, going from 506, along path 528 to527 and back to the MP. If it is intact, it shows that both unit 1A and8B are functional. If it is not, it shows that one of the two units isnot intact. The use of test signal 535, or a test signal emanating from8A could allow the distinction between the two possible malfunctions.

FIG. 14E shows (in addition to confirmation signal #1) confirmationsignal #2, going from 506, to 508, along path 530, to 525 and back to527. If confirmation signal #1 was intact and #2 was not, it wouldisolate a fault to either unit 1B or 8A. An test signal emanating“upstream” from 525 could distinguish the two possibilities.

FIG. 14F shows (in addition to confirmation signals #1 and #2)confirmation signal #3. It traverses 506, 508, 510, 512, path 532, 521,523, 525 and 527. A failure to receive confirmation signal #3 wouldoccur if either 3A or 6B failed. The two possibilities would bedistinguished by a test signal upstream from 521.

FIG. 14G shows the presence of all four confirmation signals. This isthe expected result when a system command (e.g. release PU-SU lock) isissued by the MP.

FIG. 14H shows the expected result when a command is issued whichaffects the victim. For example, the command to defibrillate wouldresult in confirmation signal #1 along path 528, confirmation signal #2along path 530, confirmation signal #3 along path 532 and confirmationsignal #4 along path 534, and the command itself along path 515. Thedelivery of the shock, resulting in an electrocardiographic change alongpath 518 would then be transmitted back to the MP as previouslydescribed.

FIG. 14J shows voice prompts, a modality for isolating and fixing aproblem with audio communication between the MP and the enabler. Byusing voice prompts, the MP can communicate over a channel that mightnot be adequate to support voice. These are discussed below.

FIG. 14K shows the presence of a backup for each hardware component ofthe system: elements 536, 538, 542, 544, 549, 551, 555 and 557, andbackup communication links 540 and 553. The figure shows a failure oflink 510 to support communication between 1B and 3A. It shows the use ofalternate link 540, in place of 510.

FIG. 14L shows the failure of confirmation signal #4, indicating afailure of either 3B or 6A. The figure also shows the test signal 535properly transmitted from 6A to 6B, indicating that the failure ofconfirmation #4 is due to a fault in 3B. FIG. 14M shows the bypassing of3B by signal 543 to backup 3B unit 544, which interacts with theenabler/victim/EMT as 514 was intended.

FIG. 14N is a flow diagram showing one possible data/commands handshake.After the completion of the CS end of the communications handshake,block 481 of FIG. 13A, indicating an “Intact Handshake Loop” leads toblock 474B, to block DC1 474A of FIG. 14N. A test command, block 560, issent through the system as shown in FIG. 14C. If, block 561,confirmation signal #4 is received, the handshake is successful and theMP sends a command to the master control unit of the PU to set MC=1,allowing him to control all aspects of the PU. This leads to block 600Band the audio handshake with the enabler.

If confirmation signal #4 is not received, the algorithm asks, block563, if confirmation signal #1 has been received, as per FIG. 14D. Ifno, the fault is either with 8B or 1A. Using the PU test signal, asdiscussed above the distinction between 8B and 1A is made.

If confirmation signal #1 has been received, the algorithm asks, block568, if confirmation signal #2 has been received, as per FIG. 14E. Ifno, the fault is either with 8A or 1B. Using the PU test signal, asdiscussed above the distinction between 8A and 1B is made.

If confirmation signal #2 has been received, the algorithm asks, block571, if confirmation signal #3 has been received, as per FIG. 14F. Ifno, the fault is either with 6B or 3A. Using the PU test signal, asdiscussed above the distinction between 6B and 3A is made.

If confirmation signal #3 has been received, the fault is either with 6Aor 3B. Using the PU test signal, as discussed above the distinctionbetween 6A and 3B is made.

Once the faulty component is localized, various compensatory processescan be performed. These may involve changing gain, filtering, noisesuppression, modulation, bandwidth or other techniques as are known inthe art. They may also involve switching to a backup component, asdemonstrated in FIG. 14M.

If the data/commands handshake has not succeeding, the MP decides, block566, whether to continue his efforts to remedy it. If he decides to doso, another test command is sent, block 560. If he decides not to hisoptions, box 567, include a) a repeat of the communications handshake,with or without changes in communications routing/modality, b) retryingafter the PU is in a slightly different location, or c) going to AEDcontrol and, if possible, monitoring PU events while trying to establisha better handshake.

The data/commands handshake during diagnostic testing is shown in FIG.14O. It is functionally similar to the non-testing version in 14N. Itsinput is from 492B, FIG. 13B. If successful, it results in thetransmission of a command to set MC=4. Troubleshooting is identical toFIG. 14N. If the MP chooses not to continue after a failed attempt(s),box 587, the options, besides starting from a new communicationshandshake, include dispatching a maintenance person to the PU and/ornotifying PU site personnel.

Other data/commands handshakes are possible including:

a) those based on using a top-down approach in which, if confirmationsignal #4 is not received, confirmation #3 is sought; and if notreceived #2 is sought etc.;

b) those based on using a bottom-up approach in which, confirmationsignal #1 is first checked for. If confirmation signal #1 is notreceived, confirmation #2 is sought; and if not received #3 is soughtetc.;

c) approaches in which a large number of sources of test signals indifferent places along the communications loop allows the isolation of afault. Such a format could also use either a top-down approach or abottom-up approach.

In practice, the signal assessments and the entire handshaking processcould be extremely rapid.

5.3 Audio and Informational Handshakes 5.3.1 Part I, Audio Handshake

The output of the data/commands handshake leads to the audio handshake,block AH 600A, FIG. 15A. If, block 601, traversing this handshake forthe first time, block 602B results in the MP identificationannouncement. Three methodologies are shown in FIGS. 15B through 15H,corresponding to the three outputs of blocks 661 and 662. With oneapproach, using voice prompts, block 602B leads to 661 to 605B TO 605AFIG. 15B. For the two approaches without voice prompts, block 602B leadsto block 661 to 662 and to either 606B, 606A (FIG. 15D) or 663B, 663A(FIG. 15E. If the MP has already been through the protocol, but hasreturned to it because of an interruption in communications he has theoption 602A to recheck audio integrity or to bypass this step.

5.3.2 Audio Handshake, Part II 5.3.2.1 Using Voice Prompts

The MP starts by asking the EN “Can you hear me clearly?” block 606. IfEN answers “YES”, block 607 leads to 608 where the MP assesses thequality of the EN voice at the CS. If it is good, then adequatebidirectional audio has been achieved which leads to DD FIG. 16A and theinformational handshake.

If at 608 the quality of EN's voice at the CS is inadequate, MP optionsinclude, (block 609B) 4A, 5A, 5B, 6A and 8B. The MP then, 610 asks EN tospeak, and reassesses the quality of EN's voice at block 611. If stillinadequate and, at 612, he wishes to persist with audio efforts, the MPproceeds through another loop of 609 (selecting another communicationsenhancement), 610, and 611. If he decides to abandon efforts at two-wayaudio communication, the protocol leads to 613A, FIG. 15G.

If, at 607, the EN answer was either “NO” or there was no response, theMP issues, at 615, a voice prompt, VP, asking if the EN can hear the VP.If, at 616, the answer is yes, the best MP options, block 616A, forimproving audio communication are 1A and 3B. The MP himself then asksagain, at 617, if the EN can hear him clearly. If, at 618, the answer isYES, he returns to 608. If the answer is “NO” he decides whether tocontinue with audio efforts, block 620. If yes, he repeats the loop ofblocks 616A, 617, 618 and, if necessary, 620. If no, he proceeds to VP760A, FIG. 15F. If the EN answer at 616 was “NO” or “NOT CLEARLY” thebest options are 3B and 4A. He selects at block 616B, and issues anotherVP at 621. If the EN answer is “YES”, the protocol returns to 617. Ifthe answer is “NO” the EN must decide 623 whether to persist with audio.If yes, he repeats the loop 616B, 621, 622 and possibly 623. If no, heproceeds to VQ 770A, FIG. 15H.

If at any of blocks 616, 622 or 618 there is no EN response, theprotocol goes to T 619A, FIG. 15C. At 624, if the MP does not hear theVP, he decides at 625 to either continue audio efforts (options 6A or8B), block 626 leading to Q 615A or does not, leading to VS in FIG. 15H.If the MP does hear the VP then block 628 lists five possible reasonsfor no EN response. AT 629, the MP decides which of these five is mostlikely leading to one of 630A-630E. His options then range fromcontinuing to use electronic means of enhancement, to asking the EN touse the wireless headset in the PU tool-kit to calling 9-1-1 in theevent of suspected prank. If he wishes to persist with audio efforts, hereturns to Q 614A (FIG. 15B) and tries the VP again. If he wishes to usea non-audio format he goes to VU 634A of FIG. 15H.

5.3.2.2 Without Voice Prompts, Version 1

If the MP uses this approach, 662 leads to PP 606A to 639 where the MPasks: “CAN YOU HEAR ME CLEARLY?” If the EN answer is “YES”, then thesequence 647, and either 648A or 648B, 649, 650, 651 is identical to thesequence 608, and either 609A or 609B, 610, 611, 612 in the Voice Promptversion of Part II, discussed above in Section 5.3.2.1. The exit pointsare also identical.

If, at 640, there is no response, the protocol proceeds to 652 withcascade of options 654A to 654E which parallel those in the VP Section5.3.2.1 above, emanating from 628 and 630A-630E. The endpoints for thisbranch of the protocol are also VU 634A if the MP decides to seek textcommunication. If he persists with audio efforts, he returns to block PP606A. If at 640 the EN response was “NO” the MP options are, block 641,1A, 3B and 4A. After again asking, at 643, if the EN can hear him, hecan go to either:

a) another loop through 641, 642, 643 if the EN answer is “NO” and theMP wishes to persist with audio;

b) 652 if there is no EN answer, and proceed as previously described; or

c) go to VQ 770A, FIG. 15H.

5.3.2.3 Without Voice Prompts, Version 2

This approach is very similar to that discussed in 5.3.2.2 except thatat block 640, the MP tries either option 3B or 4A, block 691, and againasks “CAN YOU HEAR ME CLEARLY?”, block 692.

There are three possible responses:

a) If there is still no response, he proceeds 682 to 683 to a cascade ofoptions which are identical to 652, 653 of version 1 without VP.

b) If the answer is “YES”, he returns to the same loop that wasencountered in both previously discussed versions of Part II in whichthe EN can hear the MP, and the MP's ability to hear the EN is underevaluation.

c) If the answer is “NO”, this leads to □ 694A and a decision, 675 toeither abandon the current audio effort VQ 770A, FIG. 15H, or to loopthrough 671, 672, 673 and 675 after trying one of options 1A, 3B or 4Aagain.

5.3.3 Audio Handshake, Part III

In Part III of the Audio Handshake Protocol, the MP acknowledges thateither one or both arms of his communication with the EN will requiretext format, and that it is possible that communication may not at allbe possible. The MP uses the video screens on the PU. If he can hear theenabler, but the enabler can not hear him, or hears him marginally(protocol entry points VQ and VU) he can communicate by sending textmessages to the EN, and having the EN speak his responses, block 745,FIG. 15H.

In the opposite situation, where he cannot hear the enabler, but theenabler can hear him, block 734, they can communicate by having the MPspeak directly to the EN and by having the EN send text messages on oneor both of the PU touch sensitive screens. If neither side can hear theother, they can communicate by two-way text messages, as shown in block757, FIG. 15H.

In the voice prompt variants of the protocol, the enabler may be able tohear the voice prompts better than a garbled or distorted version of theMP's voice, if communication conditions are poor; The MP may be able tohear the EN well enough, blocks 706 and 707, or may ask the EN to usethe touch sensitive PU screen, block 717. These are shown in FIG. 15F.

One outcome arm, block 716 results in the EN only being able to hearvoice prompts, and the MP hearing the EN only marginally. Although thisis a sub-optimal outcome, it is still better than MC=2, i.e. switchingto AED function, since in that case, the EN also hears voice prompts butdoesn't have the benefit of the MP in charge of the situation. Eventhough voice communication is marginal, the narrower bandwidth whichwould support ECG and command transmission, having already beenevaluated during the data/commands handshake, would suffice.

5.3.4 Informational Handshake

Having established an adequate communication modality leads to DD 774Aand the start of the informational handshake, shown in FIG. 16A. The MPmust know determine the reason for the Button Press, and whether it isreasonable to release the PU for use in the current situation.

After asking the victim to describe the emergency, listening to hisanswer, asking for additional information if necessary, blocks 775 to778, the MP classifies the event in one of four categories using thealgorithm in blocks 779, 784 and 786:

a) an actual or possible cardiac emergency, 780;

b) a non-cardiac medical emergency, 785;

c) a non-medical emergency, 787B; or

d) a non emergency, 787AS.

If it is classified as a cardiac emergency, he asks the EN if he iswilling to participate 780. If the answer is “YES”, he immediately takesthe steps in box 782 including releasing the PU lock.

FIGS. 16B and 16C are directed at a backup plan for a lock releasefailure. In FIG. 16B, 790, the command to release the lock leads to 791,the attempted release and 792, an assessment. If the release issuccessful, the PU transmits a telemetry signal, block 793, whichappears on the CS event log. If unsuccessful, two more tries are made,looping over block 791, 792, 795 and 796. If still unsuccessful, afailure signal is transmitted. In either case (or in the case ofuninterpretable telemetry), the protocol proceeds to FIG. 16C

If lock release was successful, block 806A leads to 807, and the MPinstructs the EN in removing the PU. The MP should then, 808, 815receive a PU-SU separation signal, leading to start of the cardiacmanagement protocol in Section 5.4 and FIG. 17. A problem with lockrelease is handled by any one of the following options:

a) having the EN try to remove the PU even though telemetry suggeststhat it is locked in place, blocks 813, 814 and, if successful, 815;

b) re-transmitting the command to release the PU, blocks 812B, 783C;

c) telling the enabler the mechanical lock combination 816, 807, 808.

5.4 PU Transport and Setup at the Victim's Side 5.4.1 PU Transport

The MP, after a) having decided that the situation described by theenabler represents a bona-fide emergency for which the PU should beutilized, and (b) having released the PU-SU locking apparatus, will wantto give additional instructions to the enabler.

Block D 818A, FIG. 17, (reached from block 818B, FIG. 16C) leads to box819, which shows the first group of instructions. The MP has threechoices as to the timing of his giving these instructions:

a) He could give them while the enabler is transporting the PU to thevictim. The advantage of this approach is that it saves time. Theapproximately thirty seconds that it takes to deliver the instructionsin box 819 would be added to the time before victim treatment begins, ifPU transport did not begin until after their enunciation to the enabler.The disadvantage of this approach is that the enabler may not hear themas well, during transport of the PU, because the PU is further away fromhis ear than it would have been when it was attached to the PU. The MPcould compensate for this by increasing the audio volume at the PU. Hewould be guided in this process by intermittently asking the enabler ifhe, the EN, could adequately hear the MP. In a preferred embodiment ofthe invention, the presence of multiple PU speakers 146 (FIG. 6A andSection 2.1), each of which projects in a different direction, optimizesthe chance of good reception. Another potential disadvantage of thisapproach is that the quality of the audio communication between the MPand the EN may not be as good as when the PU was attached to the SU. Ina preferred embodiment of the invention, the presence of redundancy inthe communication, makes this scenario unlikely to occur.

b) The MP could give the instructions in box 819 before he releases thePU. Having already established good communication with the EN, the MPwould be assured that the instructions were received. However, the delayimplicit in this approach makes it undesirable unless the situation isnon-urgent.

c) Hybrid approaches involve giving as much of the instructions aspossible in the moments while the PU is being detached from the SU. Tofacilitate this, a truncated version of the contents of box 819 (e.g.“Carry this unit to the victim's side as quickly as possible.”) couldfirst be given as the PU is being detached from the SU.

In Section 4.4.2, the calculation of the time for transportation of thePU to the victim is discussed. In that discussion and during the SampleCardiac Arrest (Section 4.2, Table 11, Time 0:56 to 1:37), variousestimates are made including a 2.5 mile per hour walk rate whilecarrying the PU and a 50 yard distance. These result in a hypothetical41 second transport time. In actuality, both shorter and longertransport times will occur.

If the EN arrives at the victim before the completion of the MP'snarration of the contents of box 819, the MP can: a) accelerate hisdelivery of the instructions; and/or b) truncate the contents (sincesome of the instructions may be repeated after the EN has arrived at thevictim's side).

Box 820 contain additional dialog that would be appropriate—timepermitting—during the transport of the PU to the victim. None of thedialog is absolutely essential, (orientation instructions for the PUhaving been given in box 819,) so that if the EN arrives at the victimbefore any or all of the contents of box 820 is completed, it can bedeferred.

The enabler would have already given a very brief version of what heknows of the victim situation during EN's initial dialog with the MP. Ifthere is time during PU transport, the MP may ask the EN for moreinformation (if known) about either the victim's past medical history orthe current victim situation. The MP may also ask whether the EN has hadany experience in the administration of first aid. The MP givesassurance to the enabler, as indicated in box 820, that the MP can guidean inexperienced person through the steps needed to allow the assessmentand treatment of the victim, and that an emergency medical team has beensent for. Orientation instructions for proper placement of the PU may berepeated at this time.

Following box 820, block 823B leads to FIG. 18, the flow diagramsshowing PU arrival and setup.

5.4.2 PU Arrival at Victim; PU Setup 5.4.2.1 PU Touchdown and VideoSetup

The flow diagram of FIG. 18A corresponds to the events which take placeupon the arrival of the enabler with the PU, at the site of the victim.

The events it shows begin with block OA1 823A which follows block 823B(FIG. 17). In blocks 824, 825 and 826:

a) The EN tells the MP that he has arrived at the victim;

b) The MP reminds the EN of the proper method of placing the PU; and

c) The EN puts the PU down next to the victim.

Blocks 824 and 825 are optional. Having previously been instructed inproper PU placement, the EN may perform this task on arrival without thedialog referred to in boxes 824 and 825.

If the PU was properly placed on a surface next to the victim (handlesand screens facing upwards), block 827, the PU removal/touchdown sensors178 (FIG. 8), acting like push-button switches, cause the PU to generatea touchdown confirmation signal (see Section 2.3). The touchdowninformation:

a) causes the PU to release the lock which secures the PU tool-kit door158 (FIGS. 6A and 6B); and

b) is transmitted by the PU to the central station, block 828A, where itis displayed, on the Portable Unit Deployment Screen (see FIG. 27) andobserved by the MP, block 829. These immediately aforementioned eventsoccur from 1:41 to 1:42 during the Sample Cardiac Arrest (Table 11).

If, after the EN has placed the PU, the MP does not receive thetouchdown confirmation signal, block 828B, he has two choices, block831:

a) He can quickly further instruct the EN in proper PU placement, block832A, returning to block 827, where once again the issue of correct PUplacement is addressed; or

b) He can send a tool-kit door release signal, block 832B.

If PU placement was sub-optimal and if audio communication between MPand EN is sub-optimal (discussed in the following section), preventingeasy communication of placement instructions by the MP, the MP willchoose to release the tool-kit door. The wireless headset contained inthe tool-kit would then be available to the EN which would possiblyfacilitate communication and PU placement.

Once the MP is satisfied with PU placement, he can set up (block 830)the PU video camera. In a preferred embodiment these steps include:

a) sending one or more signals to the PU to extend the video boom 112(FIG. 6B) and to properly orient it (see discussion of FIG. 28) so thatthe MP can see the victim; and

b) adjusting parameters of video quality such as brightness, contrast,focus, etc. (upper right hand portion of FIG. 28). Although the processof video camera adjustment is presented before the section on audiocommunication adjustment hereinbelow, the two adjustments would beperformed simultaneously, in order to maximally shorten theresuscitation time.

Following the events described in this section, block 833B leads toblock OA5 833A (FIG. 18B) at which time audio communication adjustments,if needed, are performed.

5.4.2.2 Audio Communications Adjustment, If Necessary 5.4.2.2.1 AudioCommunications Overview

Though MP may make audio adjustments at anytime during his exchange withthe enabler or emergency personnel, the most likely times for suchadjustments would be:

a) immediately after the MP and the EN begin speaking;

b) during the time that the EN is transporting the PU to the victim; and

c) shortly after the of the EN and the PU arrive at the victim's side.

Adjustments of what the EN hears (“EN audio”) may involve one or moreof:

a) increasing the audio volume by increasing the gain at the PU;

b) various other electronic enhancements of EN audio such as:

-   -   i) changing the emphasis of different audio frequency components        at the PU;    -   ii) changing the noise suppression at the PU;    -   iii) changing the bandwidth allocation for EN audio;    -   iv) changing type of modulation, channel or routing of EN audio;        and    -   v) changing EN audio signal processing at the CS end.

c) switching from the PU speaker 146 and microphone 148 combination to awireless headset 168 (FIG. 7A) in the PU tool-kit, and adjusting one ormore of the parameters which affect the quality of EN headset audio.

Adjustments of what the MP hears (“MP audio”) may involve one or moreof:

a) increasing the audio volume at the CS;

b) various other electronic enhancements of MP audio such as:

-   -   i) changing the emphasis of different audio frequency components        at the CS;    -   ii) changing the noise suppression at the CS;    -   iii) changing the bandwidth allocation for MP audio;    -   iv) changing type of modulation, channel or routing of MP audio;        and    -   v) changing audio signal processing at the PU end.

c) switching from the PU speaker 146 and microphone 148 combination to awireless headset 168 (FIG. 7A) in the PU tool-kit.

The MP controls the above parameters by using the Communication andMaster Control Screen shown in FIG. 25 (via menus such as “CHANGECENTRAL STATION RECEIVER PARAMETERS” and “CHANGE PORTABLE UNIT RECEIVERPARAMETERS”).

5.4.2.2.2 Audio Communications Flow Diagram Following PU Touchdown

FIGS. 18B and C shows the communications adjustments when the PU isplaced at the victim's side. Block OA5 833A (reached from block 833B,FIG. 18A) leads to block 834 where the MP:

a) asks the enabler if he, the enabler can hear the MP well;

b) optimizes EN audio;

c) reassesses his own audio (i.e. MP audio); and

d) optimizes his own audio.

If both enabler and MP audio are adequate, block 835 leads to block 850Bwhich leads to block OA2 850A of FIG. 18D, the beginning of victimassessment by the MP. If either the EN audio or the MP audio isinadequate, the MP, at block 836, decides whether to continue withefforts to adjust the audio. If he decides not to continue, block 836leads to block 842B, then to block OA6 842A (FIG. 18C), which leads tonon-audio communication methods. If he decides to continue with effortsto optimize audio, at block 837 he has the option of asking the EN touse the wireless headset. If the MP decides, instead, to continue tooptimize the audio without resorting to the headset, block 837 leads toblock 838A—an adjustment of one or more of the aforementioned audioparameters—which then leads back to block 834 and a reassessment of theaudio quality.

The wireless headset contains both a microphone and one or twoearphones. If, at block 837, the MP decides to have the EN utilize thewireless headset, the MP, at block 838B:

a) asks the EN to remove it from the toolkit and put it on;

b) speaks with the EN through the headset; and

c) optimizes both MP and enabler audio.

If both enabler and MP audio quality are then adequate, block 839 leadsto block 850C which leads to block OA2 850A of FIG. 18D, the beginningof victim assessment by the MP. If either the EN audio or the MP audiois still inadequate, the MP, at block 840, decides whether to continuewith efforts to adjust the headset audio. If he decides not to continue,block 840 leads to block 842C, then to block OA6 842A (FIG. 18C), whichleads to non-audio communication methods. If he decides to continue withefforts to optimize audio, block 840 leads to block 841—an adjustment ofone or more of the headset audio parameters—which then leads back toblock 839 and a reassessment of the audio quality.

5.4.2.3 Non-Audio Communication Backups

If MP attempts to optimize audio communication with the enabler areunsuccessful, there are, in a preferred embodiment of the invention,multiple backup options, as indicated in FIG. 18C. If the MP was notable to optimize enabler audio and/or MP audio, blocks 842B and 842C(FIG. 18B) lead to block 842A (FIG. 18C). Then, if the enabler cannothear the MP, block 843, the MP may use either voice prompts(pre-recorded short messages held within the PU memory) or video prompts(text messages shown on PU screens 156 [FIG. 6A and right hand portionof FIG. 10]). If the MP cannot hear the enabler, block 844:

a) The MP can ask the enabler to respond to MP questions using atouch-sensitive screen based virtual keyboard 156 (see right handportion of FIG. 11), where the enabler

-   -   (i) provides yes/no responses (e.g. by touching “YES” 370 or        “NO” 371 on the PU touch sensitive screen);    -   (ii) answers questions in a multiple choice format (e.g. by        touching “A”, “B” or “C” 372 on the PU touch sensitive screen);        or    -   (iii) answers questions with text messages (e.g. by using a        standard keyboard arrangement 369), if the yes/no or multiple        choice formats are inadequate; or

b) The MP can use speech recognition techniques, as are known in theart, using software which runs on the PU microprocessor (see below), andthereby encode the answers to MP questions, after which the codedresponse is transmitted to the CS.

If both EN audio and MP audio are inadequate, then the MP may use one ofthe techniques listed in block 843 and one of the techniques in block844 to establish non-audio two-way communication.

Blocks 843 (EN non-audio options) and 844 (MP non-audio options) eachlead to block 845. If the MP, is satisfied that proper two-waycommunication with the enabler is established (albeit non-audiocommunication in one or both directions), block 845 leads to block 850D,and then to block OA2 850A (FIG. 18D), the start of victim assessment.

If the MP is not satisfied with the communications, he sends a commandto the PU which sets the master control unit 130 to state 2 (MC=2),block 846, which enables the AED/P i.e. the automatic externaldefibrillator/pacer. This allows the PU to function without MP guidance(see Section 1.3.1.2), in a manner known in the art. During the timethat the PU is functioning in this automatic mode: a) the MP continuesto try to establish a better communications link with the enabler, block847; and b) the MP may monitor PU activity, including ECG and AEDactivity, if these are transmitted to him with adequate quality.

If adequate two-way communication between the MP and the enabler islater established, block 848, the MP sends a command to the PU whichsets the master control unit to state 1 (MC=1), block 849, whichdisables the AED/P and returns control of the PU to the MP. This leadsto block 850E, block OA2 850A and victim assessment. If, however, duringthe period of communication blackout the AED/P-directed resuscitationeffort had proceeded to a point beyond initial victim assessment (e.g.to ECG analysis or defibrillation therapy), then block 849 would lead tothe appropriate later point in the flow diagrams (e.g. block G 900A[FIG. 19] or block M 914A [FIG. 20]).

As long as proper two-way communication between the MP and the enableris not reestablished, the effort to do so goes on, with block 848leading back to 847, and again to 848, in a continuously repeating“loop”.

The aforementioned is not intended to represent the only possiblesequence of steps in the establishment of non-audio communication. Otheroptions include but are not limited to:

a) not attempting any of the non-audio communication means delineated inblocks 843 and 844;

b) attempting some but not all of the non-audio communication meansdelineated in blocks 843 and 844; and

c) having block 848 lead back to block 834 (FIG. 18B).

5.4.2.4 Initial Victim Assessment

The medical treatment of a conscious person is far different than thatof an unconscious one and therefore, the MP must determine the victim'sstate of consciousness.

After having established that his communication is adequate block OA2850A, the MP determines the victim state of consciousness by asking theenabler 852 and using both the enabler response 853 along with his ownassessment 854. If the victim is unconscious or if there is uncertaintyabout his state of consciousness, block 855 leads to 867B or 867C, eachof which leads to block OA3 867C and defibrillator pad application.

If the victim is conscious, block 856 leads to three possible MPchoices:

a) He can decide 857 that ECG electrodes, “mini-pads” should be placedon the victim's extremities so that an ECG can be recorded to furtherassess the victim. Block 868B leads to block OA4 868A, FIG. 18E.

b) He can decide 859 that the victim is, despite being conscious,potentially in need of a shock or pacing, either at that time or in thenear future, and that therefore application of a standardpacing/defibrillation pad is in order. Block 867D leads to block OA3867A, FIG. 18E.

c) He can decide 858 that ECG hookup is unnecessary, at which point hisoptions 860 include either the termination of victim assessment 861A oran assessment of the victim's blood pressure and/or oxygen saturation.In case of the latter, he advises and instructs the enabler 861B in theattachment of these devices (located in the PU tool-kit). Once heobtains this additional information he decides 862 either (i) that nofurther victim assessment is needed 863A, (ii) that a continued periodof blood pressure and/or oxygen saturation is needed 863B, returning to862 (and ongoing reassessment until he decides otherwise or the victimscondition changes), or (iii) that ECG monitoring is now needed 865, inwhich case he must further decide 866 if the electrode pads are to bemini-pads, block 857 leading to blocks 868B and OA4 868A, or standarddefibrillator pads, block 859 leading to 867D to OA3 867A.

5.4.2.5 Electrode Pad Application

FIG. 18E shows two algorithms for electrode pad application, in aparallel display format. The left side of the figure shows mini-padapplication; The right side shows standard defibrillation padapplication. The instruction procedure for each is similar.

The MP starts by telling the enabler of the task (baring the extremities[in the case of mini-pads] or the chest [in the case of standarddefibrillating/pacing pads) to be performed, blocks 871 (in the case ofmini-pads) and 876 (in the case of large pads). The MP then checks,either by asking or by direct visual observation, that the task has beenperformed, blocks 872 and 877. If performance is unsatisfactory, heprovides further instruction, blocks 873A and 878A and continues torepeat the cycle of instruction and evaluation until he is satisfied.The MP then advises the enabler to open the PU tool-kit and remove theappropriate pad, blocks 873B and 878B. The MP demonstrates proper padapplication for the enabler on the PU screen, blocks 874 and 879 (seebelow, Section 6.2.2 and FIG. 28). The MP verbal or text instruction forpad application is shown in blocks 875 and 880.

With the pad(s) having been applied, the two paths through the flowdiagrams reunite at block 883B and proceed to the electrode padassessment. If at any point, the heart rhythm or clinical status of avictim with mini-pads deteriorates, the application of defibrillationpad(s) would be a consideration, necessitating a second pass through theelectrode pad application routine, this time starting at block OA3 867A.

5.4.2.6 Electrode Pad Assessment

The assessment begins with visual assessment of the adequacy of padapplication. The MP proceeds by asking the enabler 884 and using boththe enabler response 885 along with his own visual assessment 886. If,block 887, pad application is grossly inadequate, the MP furtherinstructs the enabler 888, then visually reassesses pad application andthe cycle repeats until the MP is satisfied. When the MP is satisfied,impedance measurements are made 890 to assess the pad electrically, withthree possible outcomes:

a) If the measurements are all satisfactory, the MP assesses ECG quality896. If satisfactory, he goes ahead to the first tier arrhythmia triageprotocol via block 900E. If only some are satisfactory, he decides 897either (i) that the situation is “good enough”, feeling that the extratime expenditure to achieve a better result is not likely to bejustified, and proceeds to block 900E, or (ii) that he will ask theenabler to improve pad application. If so, he may use the impedancemeasurements and/or ECG signal quality to identify one or more areaswhich are making poor contact, and either let the enabler know thelocation or, block 895, show him on the PU screens. This leads to block889C, to block C2 889A and a reassessment of impedance measurements. Ifnone of the measurements is satisfactory, he decides 893 either (i) toadvise the enabler to check and secure the pad connector, block 892A toblock 889B to block C2 889A and a reassessment of impedance, or (ii) toadvise the enabler to attach another electrode pad, block 892B to block883C to block C1 883A.

b) If only some of the initial impedance measurements were satisfactory,block 894, the MP decides whether they are good enough. If yes, thisleads to block 896 and the aforementioned assessment of ECG quality. Ifno, this leads to block 895 and the aforementioned assessment ofspecific areas of poor pad contact.

c) If none of the initial impedance measurements were adequate, block891 leads to either block 892A or block 892B at which time the MP makesthe same decision as when none of the ECG tracings were adequate.

In practice, the aforementioned sequence of steps can happen veryquickly. If pad application was done well, the chance of a satisfactoryquality ECG is high. If ECG quality is high from the start, astreamlined approach could skip the visual assessment and/or theimpedance measurements. However, the pad application requirements foroptimum defibrillation exceed those required for ECG recording.

5.5 Flow Diagrams: Arrhythmia Management 5.5.1 First Tier ArrhythmiaTriage Protocol 5.5.1.1 Overview

FIG. 19, the First Tier Arrhythmia Triage Protocol, shows an approach toMP decision making in the moments immediately after theelectrocardiogram information becomes available to him. (Otherapproaches to this tier of triage are possible, see Section 5.5.1.3,below.)

Hereinbelow, a rhythm which is paced by the victim's own pacemaker orimplantable defibrillator is classified and referred to as eithernormal/nearly normal, or bradycardia, based on the resulting rate.“Pacing” or “a paced rhythm”, unless otherwise specified, refers toexternal pacing. Although the traditional electrocardiographicdefinitions of bradycardia (rate less than 60) and tachycardia (rategreater than 100) are possible set-points, the MP is ultimately guidedby his judgment, as to whether to classify a rhythm as a bradycardia ortachycardia. A well tolerated rate of bradycardia or tachycardia wouldnot necessitate treatment.

There are two inputs to FIG. 19. The principal input is block G 900A,which is arrived at from FIG. 18C, after a successful electrode padapplication to the victim results in a satisfactory quality ECG. The MPthen interprets the ECG, leading to five possible outcomes:

a) bradycardia or an externally paced rhythm (leads to FIG. 21);

b) a tachycardia requiring a shock, i.e. ventricular fibrillation (VF),poorly tolerated ventricular tachycardia (VT) or poorly toleratedsupraventricular tachycardia (SVT) (leads to FIG. 20);

c) a well tolerated tachycardia not requiring a shock (leads to FIG.22);

d) a normal or near normal rhythm;

e) a rhythm which can not be interpreted in an unequivocal manner,either because of sub-optimal signal quality, or because even a perfectelectronic representation of the rhythm would still result inequivocation.

Each of the first three outcomes leads to a different flow diagram, seebelow. A normal rhythm results in continued looping through FIG. 19, asthe MP continuously monitors the victim's rhythm after the initialassessment of it. If the rhythm is not unequivocally interpretable, theMP has a variety of choices which are discussed below.

The second input to FIG. 19 is block GG 924A. If the victim has abradycardia which does not require treatment, then theBradycardia/Pacing Protocol (FIG. 23 [entered from block 904B of FIG.19]) leads back to FIG. 19 via block GG 924A. Further monitoring of sucha “nearly normal” rhythm is discussed below.

5.5.1.2 Details of Arrhythmia Triage 5.5.1.2.1 Bradycardia/Paced RhythmDecision

The availability of an ECG signal leads to block G 900A, which leads toblock 902 at which the MP decides if the rhythm is a bradycardia or apaced rhythm. There are three possible outcomes:

a) If it is either a bradycardia or a paced rhythm, the MP goes to theBradycardia/Pacing Protocol (FIG. 21), as indicated by block 904B.

b) If it is neither a bradycardia nor a paced rhythm, the MP proceeds toblock 906 for a tachycardia triage decision, discussed (see Section5.5.1.2.2, below).

c) If the rhythm is uncertain the MP chooses from three options, shownin box 908 (see Section 5.5.1.2.3, below).

5.5.1.2.2 Tachycardia/No Tachycardia Decision

At block 906, the MP decides if the rhythm is either a tachycardia whichrequires treatment, or a rhythm which is normal, or nearly normal andwhich therefore requires no treatment.

If the rhythm is a tachycardia which requires treatment, the MP—at block912—quickly reassesses whether the victim is conscious or unconscious,since one generally does not wish to administer a shock to a consciousvictim. The MP performs this assessment by either speaking with theenabler, by making his own audio and video observations (FIG. 18D), orboth. In cases where the rhythm is either VF, poorly tolerated VT, orpoorly tolerated SVT, the victim will be unconscious and the MP proceedsto the Shock Administration Protocol, FIG. 20, via block 914B.

If the victim is conscious during a tachycardia (in which case itcannot, for all practical purposes, be VF), the MP—at block916—instructs the enabler in the attachment of the blood pressure cuffand blood oxygen saturation sensor. (If the enabler has alreadyperformed this, i.e. during a previous pass through the protocol, thestep in block 916 is skipped. The MP then proceeds to the Second TierArrhythmia Triage Protocol, FIG. 22, via block 918B.

If, at block 906, the MP decides that the rhythm requires no treatmentat that moment, the rhythm is classified as normal or nearly normal. TheMP—at block 920—instructs the enabler in the attachment of the bloodpressure cuff and blood oxygen saturation sensor. (The step in block 920is skipped if these devices have been previously attached.) Next, asshown in block 922, the MP further instructs the enabler, if necessary,(e.g. in the administration of CPR) and continues to monitor thevictim's ECG. The protocol for continued monitoring is identical to theaforementioned, and, accordingly the flow diagram indicates a return toblock G 900A via block 900B.

5.5.1.2.3 Options in the Event that the Rhythm Diagnosis is Uncertain

If the MP, upon initially analyzing the ECG, is uncertain as to thecorrect rhythm diagnosis, he may either make an empiric decision totreat based on his best guess as to the rhythm diagnosis, or he may takesteps to improve the signal quality and then attempt diagnosis again. Inthe case of an empiric decision to treat, if the MP thinks that therhythm is most likely to be either VF, VT or SVT (choice #1 in box 908)he would proceed to block K 910, in preparation for treatment; If the MPthinks that the rhythm is most likely to be a bradycardia (choice #2 inbox 908), he would proceed to the Bradycardia/Pacing Protocol, FIG. 21,via block 904B. If the MP wishes to try to electronically improve thesignal quality before making his rhythm assessment (choice #3 in box908), he has a number of options including:

-   -   i) increasing the ECG gain at a number of possible points in the        system including within the PU, within the SU or within the        central station;    -   ii) changing the ECG signal filtering at any of the        aforementioned points within the system; alternatively the MP        could use other noise reduction techniques to improve signal        quality; and/or,    -   iii) improving signal quality by causing the PU to sample the        signal more frequently, or to use a greater number of bits per        sample, and, if necessary, to allocate a greater bandwidth for        the ECG signal, or to use other techniques as are known in the        art to allow for the transmission of a greater amount of ECG        information from the PU to the CS.

If the MP decides to improve signal quality, he then returns to block G900A and reassesses the ECG.

5.5.1.3 Other Approaches to First Tier Arrhythmia Triage

The first tier of arrhythmia triage shown in FIG. 19 and discussed aboveis subject to a number of variations Possible variations include:

a) having the MP make the tachycardia/no tachycardia decision before thebradycardia/no bradycardia decision;

b) having the MP make one single selection among four choices:bradycardia, tachycardia, normal/nearly normal rhythm, or uncertainrhythm; rather than making the selection—as shown in FIG. 19—in twosteps;

c) having the MP make one single selection among five choices:bradycardia, poorly tolerated tachycardia, well tolerated tachycardia,normal/nearly normal rhythm, or uncertain rhythm; rather than making theselection—as shown in FIG. 19—in three steps; and

d) merging the first tier and second tier (see below) components ofarrhythmia triage.

5.5.2 Shock Administration Protocol

The Shock Administration Protocol is shown in FIG. 20. The MP reachesthe entry point to this protocol, block M 914A from block 914B, FIG. 19,the First Tier Arrhythmia Triage Protocol.

If it is the first pass through this protocol (indicated at block 930),the MP warns the enabler that a shock is coming and that neither he noranyone else should be in direct contact with the victim (indicated atblock 932). As indicated in block 934, the MP then programs theparameters that specify the shock (see below, Section 6.3.1.2 and FIG.33) by selecting either the default choices or by selecting specificchoices of energy, synchronization, waveform and electrode pattern. TheMP then takes a last look at the ECG (block 936) to make sure that therhythm has not spontaneously changed to one which does not require ashock. If the rhythm is unchanged (block 938), the MP then administersthe shock (block 940). Following shock administration, the MP mustreassess the rhythm, indicated by block G 900C (which leads to block G900A at the top of FIG. 19, the First Tier Arrhythmia Triage Protocol).If, at block 938, the MP did observe a last-moment change in the rhythm,he does not administer the shock, and thus bypasses block 940, and, inthe flow diagram, is returned to the start of the First Tier ArrhythmiaTreatment Protocol.

If one or more shocks have already been administered, and the shockprotocol is re-entered because of VF, poorly tolerated VT or poorlytolerated SVT, then block 930 leads to block 942. At block 942 the MPwill need to make a decision about whether continued efforts toresuscitate a victim are to be pursued.

The decision to continue resuscitative efforts leads to box 944, whichincludes a variety of MP options:

a) changing the shock parameters by

-   -   (i) changing the energy of the shock,    -   (ii) changing the shock waveform, or    -   (iii) changing the choice of shock electrodes;

b) having the enabler change the electrode pad:

-   -   (i) by removing the currently applied ones and reapplying a new        one of the same type, but having the pad positioned or oriented        differently from the removed pad, or    -   (ii) by removing the currently applied one, and reapplying a        different type of pad or pads; and,

c) having the enabler start cardiopulmonary resuscitation (CPR) underthe guidance of the MP.

At block 946, the MP selects one of these options and causes itsexecution by inputting the appropriate commands (see Section 6.3.1.2).This leads back to block 932, in which the MP warns the enabler that heis about to administer a shock.

If, at block 942, the MP had decided not to continue with resuscitativeefforts, the rhythm assessment and treatment protocols end at block948A. The MP would consider making a decision to terminate therapy if hewas repeatedly unsuccessful in his efforts to terminate a tachycardiawhich does not support life, if reasonable treatment options had beenexhausted, and if neither medical nor emergency personnel were on-scenenor were expected to arrive on scene. The MP is much better qualified tomake this termination decision than an enabler using an AED would be.(See below, Sections 5.5.5.2, 5.5.5.3 and especially 5.5.5.4, for adiscussion of protocol endpoint considerations in the event of failureof pacing.)

5.5.3 Second Tier Arrhythmia Triage Protocol 5.5.3.1 Overview

FIG. 21, the Second Tier Arrhythmia Triage Protocol, shows an approachto MP decision making in the event of a well tolerated tachycardia.There are two reasons why the MP might want to consider a therapy otherthan a high energy shock (referred to in the figure as “Hi Shock” {ok?})if the victim is tolerating the tachycardia First, a high energy shockis painful, and therefore is something to be avoided, if possible, inthe case of a conscious or semi-conscious victim. Second, the presenceof a well tolerated tachycardia implies that the urgency for immediatetermination of the tachycardia is lessened. In the case of ventricularfibrillation or poorly tolerated ventricular tachycardia, the need forimmediate restoration of a normal rhythm is based on the exquisitelytime-sensitive consequences of inadequate blood flow to the brain (andis based, to a lesser degree, on other considerations including bloodflow to the heart muscle and shifts in pH and potassium). But in thecase of a well tolerated tachycardia, the blood flow to the brain andvital organs may be normal or near normal, in which case gentlertachycardia termination measures, though potentially more timeconsuming, are a reasonable alternative to the hi energy shock.

5.5.3.2 Alternative Tachycardia Termination Techniques

There are four means of tachycardia termination other than a high energyshock:

a) For certain tachycardias, viz. atrial flutter and some forms ofmonomorphic VT, a low energy shock (referred to in FIG. 21 as “LoShock”) will effectively terminate the tachycardia. Shock energy valuesof 25 joules often lead to success, and values as low as ten or fewerjoules may be successful; These are to be compared with values such as200 joules for a high energy shock. Although the victim's discomfortassociated with a low energy shock is not necessarily decreased inproportion to the energy reduction (i.e. a 10 joule shock seems to bemore than one tenth as painful as a 100 joule shock), the lower energyshock may afford some reduction in discomfort.

b) Anti-tachycardia pacing is a means of tachycardia termination thatinvolves stimulating the heart at a rate which is different (andgenerally faster) than the tachycardia rate. This is generally performedfor a few seconds at a time, and entails energy application that isorders of magnitude less than a defibrillation shock. It may requiremultiple attempts (see below) and therefore is more time consuming thaneither a high or low energy shock. (See Section 5.5.4.1, below.)

c) Certain types of supraventricular tachycardia (and atrioventricularreciprocating tachycardia) may terminate if the victim performs or issubjected to so-called “vagal maneuvers,” i.e. procedures whichmomentarily alter the extent of vagal stimulation of the heart. Theseinclude coughing, the Valsalva maneuver, ice water application to theface, and other techniques. The MP has the option of suggesting one ormore of these if he feels that they are appropriate. The suggestion maybe made to the enabler or, if appropriate, directly to the victim. Whenappropriately trained emergency medical personnel are present, the MPmay suggest the performance of carotid sinus massage as another possiblemeans of tachycardia termination.

d) Trained emergency medical personnel, once they have establishedintravenous access, may administer certain antiarrhythmic drugs(discussed above) which may terminate a variety of differenttachycardias. The MP, as discussed above, may suggest such therapy.

5.5.3.3 The MP's Assessment of the Appropriateness of the Use ofAlternative Tachycardia Termination Techniques

Physicians and other medical professionals dealing with a tachycardiavictim will assess the urgency of treatment by evaluating such basicparameters as the victim's state of consciousness, the respiratorystatus and the blood pressure. Additional considerations are the heartrate, cardiac output, the duration of tachycardia, the victim's cardiachistory and recent cardiac status (if known), whether the victim appearsto be ashen or cyanotic, whether the victim is diaphoretic and thepresence or absence of ischemic findings on the ECG. The better thevictim is tolerating the tachycardia—in the opinion of the MP—the morelatitude the MP has to continue to pursue alternative, i.e.non-aggressive means of tachycardia termination.

The MP will continually reassess tachycardia toleration for the durationof time that he pursues non-aggressive means; If at any point the victimbecomes less tolerant of the tachycardia, the MP would have the optionof switching to a more aggressive means of tachycardia termination (suchas a high energy shock).

The ideal situation for less aggressive therapy would be:

a) conscious victim;

b) adequate respiratory status;

c) adequate blood pressure;

d) heart rate less than 200 BPM;

e) minimally reduced cardiac output demonstrated by the findings of acardiac output sensor;

f) short duration of tachycardia;

g) no history of heart attack or heart failure;

h) no pallor, cyanosis or diaphoresis; and,

i) no signs of ischemia on the ECG.

As indicated above in Section 5.5.1.2.2, the MP assesses the victim'sstate of consciousness either directly or by asking the enabler.

The respiratory status is assessed by oxygen saturation sensor 174 (FIG.7A)—included in the toolkit of the PU, and put on a finger of thevictim, by the enabler, under the direction of the MP. Alternative meansfor assessing the respiratory status include:

a) a carbon dioxide sensor;

b) assessing the respiratory rate and the presence or absence of palloror cyanosis by direct visual inspection via the video camera;

c) assessing the respiratory rate by asking the enabler;

d) assessing the respiratory status by measuring transthoracic impedance

Pallor, cyanosis and/or diaphoresis may be assessed via the video cameraor by questioning the enabler, or both.

The blood pressure is assessed by using an automatically inflating bloodpressure cuff 172 (FIG. 7A). The cardiac output may also be assessed bynon-invasive means, as are known in the art. The heart rate is assessedby the ECG, which also provides information about ischemia and sets alower limit to the duration of tachycardia. Information from the enableror other bystanders may provide additional information about tachycardiaduration. These individuals may also provide information about thevictim's cardiac history, if any.

In practice, the MP would use as many of the aforementioned types ofinformation as was available, in making a decision about theappropriateness of one of the less aggressive therapies.

Algorithms for selecting the appropriate technique for tachycardiatermination, incorporating the aforementioned information, arepotentially of extraordinary complexity, since a) there is potentially alarge amount of victim related information, and b) the total experienceof the MP, as well as information on arrest management and outcomes,which may be accumulating data bases may also influence the MPdecisions. One possible algorithm, based on three very importantparameters, is illustrated and discussed in the next section.

5.5.3.4 Algorithm for Considering Alternative Tachycardia TerminationTechniques Based on State of Consciousness, Respiratory Status and BloodPressure

The MP reaches this algorithm, shown in box 950 (FIG. 21) from the FirstTier Arrhythmia Triage Protocol in the event of a tolerated tachycardia,via the sequence of blocks 912, 916 and 918B (all in FIG. 19); leadingto block 918A of FIG. 21.

The lower portion of FIG. 21 shows a method of the assignment of a gradeof 0, 1 or 2 for each of the aforementioned three victim parameters.Section 5.5.3.3 discusses how the MP obtains the information needed tomake these assignments. Once a grade is assigned for each of these threeparameters, the algorithm in box 950 indicates the assignment of one ortwo possible therapies. Where a choice between two types of therapy ispossible, e.g. ATP/Lo Shock (where the MP may choose either ATP or a lowenergy shock), the MP uses his discretion (and/or some or all of theadditional information previously discussed) to decide between the twochoices.

For example, if the victim was alert (Consciousness Grade=2), had anoxygen saturation of 85% (Respiration Grade=2) and had a systolic bloodpressure of 80 (B.P. Grade=1), the MP approach indicated by box 950would be to attempt ATP, anti-tachycardia pacing.

The MP thereby selects one of three therapeutic aproaches, a high energyshock, a low energy shock or ATP. At block 952, the MP selects thedetails of the treatment (e.g. the number of joules, in the case of ashock). If ATP has been selected, block 954 leads to block 960B whichleads to block MM 960A (FIG. 22), the Anti-tachycardia pacing Protocol.If ATP has not been selected, block 954 leads to block 914C which leadsto block M 914A, the Shock Administration Protocol.

If the initial therapy administered per the above protocol does notterminate the tachycardia, but does result in more well toleratedtachycardia, the algorithm again leads to box 950, and a reassessment ofthe appropriateness of the various alternative therapies. Although box950 contains a large amount of information, the repeat assignment of thegrades for consciousness, respiration and blood pressure can generallybe performed very quickly. (The large amount of information in the boxthus reflects the complexity entailed in reducing decision making to analgorithm.)

Many different types of algorithms are possible besides the one shown inFIG. 21:

a) The cutoffs for the assignments of each of the three grades is notunique. Algorithms are possible, for example, in which the cutoffbetween a B.P. grade of 0 and of 1 is a value other than 70.

b) Algorithms are possible in which the number of possible grades forany or all of the parameters is more or less than three.

c) Algorithms are possible which are formatted as flow diagrams ratherthan the tabular format of FIG. 21.

d) Algorithms are possible in which a greater or lesser number thanthree parameters contribute to the treatment decision.

5.5.4 Anti-Tachycardia Pacing 5.5.4.1 Background

During ventricular tachycardia, the act of pacing the ventricles atrates above (and rarely, below) the tachycardia rate may result intermination of the tachycardia. This procedure is known asanti-tachycardia pacing or ATP. Although termination of a tachycardiausing ATP may take longer than termination by a shock, and although theefficacy rate of ATP is lower than that of a shock, ATP may be thedesirable approach in a conscious or semi-conscious victim, since ashock may cause more discomfort than pacing. Anti-tachycardia pacing mayalso be used to terminate other types of tachycardia includingsupraventricular tachycardia and atrioventricular reciprocatingtachycardia (a tachycardia that involves the atria and the ventricles).

The typical ATP “burst” would consist of eight beats of pacing at a rateof 20 to 60 beats per minute above the tachycardia rate. There are threepossible outcomes when a burst of ATP is administered:

a) the victim's tachycardia may terminate; or,

b) there may be no effect on the tachycardia; or,

c) the tachycardia may accelerate to one that is less well tolerated(including the possibility of fibrillation).

If the tachycardia is terminated by ATP, the result is as good as if ashock had terminated it.

If the ATP attempt did not affect the tachycardia but was, in thejudgment of the MP, well tolerated, then one or more additional ATPbursts could be attempted. The MP must therefore quickly decide:

a) if he wants to attempt ATP again;

b) if yes, does he want to make the next attempt more aggressive, lessaggressive, or of similar aggressiveness to the prior attempt; and,

c) if the answer to a) is “yes”, and having decided on the “degree ofaggressiveness”, the MP must then select from a large number ofparticular pacing options (see ahead).

A more aggressive burst is less likely to leave the tachycardiaunchanged; it is generally more likely to either successfully terminatethe tachycardia or accelerate it. One of the primary determinants ofpacing aggressiveness is the rate of the pacing.

One simple way of assuring that the pacing rate is appropriately relatedto the tachycardia rate is to use a measure related to the inverse ofrate, the cycle length. The cycle length, also known as the RR interval(i.e. the interval between R-waves on the ECG) is the time betweentachycardia beats. Since the RR interval is typically measured inmilliseconds (MSEC), and the heart rate in beats per minute (BPM), aconversion factor is necessary:

RR interval [MSEC]=60,000 heart rate [BPM]

One way of quickly selecting a burst pacing rate is to make the ATP RRinterval a percentage of the tachycardia RR interval. With such anapproach, a paced RR interval which is:

a) 70% of the tachycardia RR interval would be considered aggressive;

b) 80% of the tachycardia RR interval would be considered moderate; and,

c) 90% of the tachycardia RR interval would be considered conservative.

Using such an approach, the MP could quickly select one of the majordeterminants of the aggressiveness of his burst pacing by specifying thepercentage of the tachycardia RR interval that he wishes to use for theATP RR interval: the “% RR”. Typical values of % RR when burst pacing issuccessful, range from 75 to 88. In a preferred embodiment of theinvention, the selection of the ATP rate by the MP is based on the % RR.

5.5.4.2 Anti-Tachycardia Pacing Protocol

FIG. 22 shows one possible approach to anti-tachycardia pacing. The MParrives at the entry point to the ATP protocol, block MM 960A, from exitpoint of the Second Tier Arrhythmia Triage Protocol, block 960B (FIG.21) which corresponds to the decision by the MP to use ATP therapy.

Block 961, at the time of the first ATP attempt, leads to block 962, atwhich juncture the MP selects from among three classes of approach,based on the aggressiveness of the pacing attempt. The approach whichentails a moderate degree of aggressiveness is the selection of thedefault values of ATP parameters, block 963, which might be 8 pacedbeats at an RR interval which is 82% of the tachycardia RR interval (seeSection 6.3.2.2, below). If the MP wishes to choose a less aggressiveapproach he could choose a % RR interval which is longer than thedefault value, as indicated by block 964. The actual choice of % RR isselected, block 974, from a variety of possible values (see Section6.3.2.3 and FIG. 37 which shows the screen used by the MP forselection), e.g. 84%, 86%, 88% etc. If the MP wishes to select a moreaggressive approach than the default values, block 965, he would havetwo sets of options: a) selecting a % RR which is shorter than thedefault value, block 966A, or b) selecting an intra-burst decrement(whereby the pacing rate increases during the ATP attempt), block 966B.Each of these more aggressive approaches has its own menu of options(shown in FIG. 37), from which the MP makes a particular selection atblock 974. Having specified the details of the upcoming ATP attempt, theMP then delivers the ATP, 975, after which the protocol returns him,block 900D, to the First Tier Arrhythmia Triage Protocol (FIG. 19).

Block 961, at the time of the second and any later ATP attempts, leadsto block 967, at which point the MP selects from among three types ofapproach:

a) increasing the aggressiveness of the next ATP attempt;

b) not changing the aggressiveness of the next ATP attempt; or,

c) decreasing the aggressiveness of the nest ATP attempt.

The default approach is to slightly increase the degree ofaggressiveness with each successive pacing attempt. This is accomplishedby decreasing the paced RR interval by 10 MSEC. With each successiveattempt.

For example, treatment of a 200 BPM tachycardia with ATP parameterswhich would be typical of a default selection (see Section 6.3.2.2)would entail:

a) Since the tachycardia rate is 200 BPM, the tachycardia RR interval is300 MSEC.

b) Assuming a default % RR of 82, the RR interval of the first ATP burstwould be 0.82×300 MSEC=246 MSEC (which corresonds to a pacing rate of244 BPM).

c) Assuming a default inter-burst decrement of 10 MSEC, the second ATPburst (if needed) would be delivered with an RR interval of 246−10=236MSEC (which corresponds to a rate of 254 BPM).

d) Assuming another ATP attempt with the default setting, the third ATPburst would be delivered with an RR interval of 236−10=226 MSEC (265BPM).

Referring again to the ATP protocol shown by FIG. 22, the default 10MSEC decrease in the burst cycle length with successive pacing attemptsis depicted by the sequence of blocks 967, 970, 973B. At block 973B,maintaining the inter-burst decrement (at 10 MSEC) is the default setup.An increase in the inter-burst decrement to a value greater than 10,block 973B, would constitute an even more aggressive approach. Othermethods of increasing aggressiveness are by selecting a shorter % RRinterval than the last one to be utilized (block 973A) and byintroducing or increasing the value of an intra-burst decrement (block973C). Once the category of increased aggressiveness is selected fromamong blocks 973A, 973B and 973C, the exact choice is specified (e.g.introducing a 5 msec intra-burst decrement) at block 974 and deliveredat block 975.

If the MP wishes to leave the aggressiveness of a second or later ATPattempt unchanged compared to the previous attempt, block 967 would leadto block 969. The option categories would then include a) leaving allATP parameters unchanged, block 972A, or b) changing the number of pacedbeats, block 972B.

If the MP wishes to decrease the aggressiveness of a second or later ATPattempt, compared to the previous attempt, block 967 would lead to block968. The option categories would then include a) increasing the % RRinterval, block 971A, b) selecting an inter-burst increment (i.e. makingthe upcoming paced RR interval longer than the corresponding intervalduring the immediately previous event), box 971B, or c) decreasing oreliminating the intra-burst decrement (if one is present), box 971C.

As was the case with an ATP attempt of increased aggressiveness, withattempts of unchanged or decreased aggressiveness, the MP (working fromthe Anti-Tachycardia Pacing Parameters Screen 1350 [FIG. 37]) thenselects the particular pacing parameters, block 974, and deliverspacing, block 975. Repeat rhythm observation follows, block 900D.

5.5.4.3 Other Possible Anti-Tachycardia Pacing Protocols

The number of possible protocols for selecting ATP parameters is verylarge. Other possible approaches include Protocols

a) which do not refer to aggression but do refer directly to specificpacing parameters;

b) in which there is a programmable minimum paced RR interval;

c) in which the intra-burst decrement is not the same for each beat ofthe burst; and,

d) in which the last R to S-1 interval (FIG. 37) varies.

Approaches to tachycardia management which do not includeanti-tachycardia pacing are possible.

5.5.5 Bradycardia/Pacing Protocol 5.5.5.1 Overview

If bradycardia or a paced rhythm is encountered during the First TierArrhythmia Triage Protocol, block 904B (FIG. 19) leads to block H 904A,the entry point to the Bradycardia/Pacing Protocol (FIG. 23). At block977, the protocol bifurcates, depending on whether external pacing is inprogress. If it is not in progress, block 978, the MP decides whether toimplement it and, if pacing is to be implemented:

a) the pacing parameters;

b) whether capture of paced impulses is properly occurring; and,

c) whether sensing of non-paced impulses is properly occurring.

If pacing is in progress, block 979, the MP has the options of:

a) continuing it;

b) stopping it; and,

c) briefly interrupting it to assess the underlying rhythm.

In a preferred embodiment of the invention, the MP may, at times, needto make a decision about ending a resuscitation effort. (This wasdiscussed, above, in Section 5.5.2 for the case of incessant ventricularfibrillation.) The situation in which the victim does not respond topacing is discussed below, in Sections 5.5.5.2, 5.5.5.3 and 5.5.5.4.

5.5.5.2 External Pacing Not in Progress; MP Decision Whether to StartPacing

At block 978, the MP makes a selection among three possible approaches:

a) If the bradycardia is mild, he may decide that treatment isunnecessary or undesirable. This leads to block 924B, returning to theFirst Tier Arrhythmia Treatment Protocol, block GG 924A (leading toblock 920, discussed above in Section 5.5.1.2.2).

b) If the bradycardia requires pacing, the MP, at block 980, decideswhether to use the default pacing parameters. If he decides to use them,block 981A, he selects this choice on a screen, keyboard, or otherinputting device. In a preferred embodiment of the invention, he makesthe selection by touching “ALL DEFAULT VALUES” (element 1372) on thetouch sensitive Main Pacing Screen (FIG. 38), as was the case during theSample Cardiac Arrest (Section 4.2, Table 11, Time 2:46). If he wishesto choose non-default parameters, block 981B, he makes his selections(as per, for example, Table 11, Times 2:57, 2:58 and 2:59) for each ofthe pacing parameters. After the selection of either default ornon-default pacing parameters, the MP checks, at block 982, to see ifpacemaker capture (electrical activation of the heart following thepacemaker impulse) is occurring. If capture is occurring, the MP mayhave or want the opportunity to determine if sensing (inhibition of thepacemaker when there is an underlying rhythm of adequate rate) isproper, block 983, using techniques known in the art. There are fourpossible outcomes following the assessment of capturing and sensing:

-   -   (i) Both capturing and sensing are proper, in which case block        983 leads to block 924C and a return to the First Tier        Arrhythmia Triage Protocol. The return is consistent with the        need for essentially continuous reevaluation of the rhythm        during the time that the MP is monitoring the victim. If the MP        had selected pacing parameters or a default set of parameters in        which external signals do not reset the timing of pacing (i.e.        asynchronous pacing, or sensing=off), then sensing at block 983        is defined (for the operation of the flow diagram) as adequate.    -   (ii) Capturing is intermittent or is not occurring at all, and        the MP wishes to continue efforts to pace. In this case, block        982 leads to block 984 and then a return to block 981B at which        point the MP would make an alteration in either the pacing        amplitude, the pacing waveform or the pacing electrodes. Capture        would then be reassessed, block 982.    -   (iii) Capturing is satisfactory, but sensing is not.        In this case block 982 leads to block 983 which leads to block        981B and a readjustment of sensing parameters: either an        increase in sensitivity or a change in the sensing electrodes        (see below), followed by a reassessment of pacing at block 982        and sensing at block 983. Alternatively, the MP may choose to        ignore an occasional failure to sense, in which case block 983.        If there are no events to sense once pacing is initiated, the MP        has the options of either proceeding with pacing, or transiently        slowing the pacing rate to further assess sensing.    -   (iv) Capture is not occurring, the MP has exhausted all possible        means of achieving capture, and neither medical nor emergency        personnel are on-scene nor are they expected to arrive on scene.        The MP may, at this juncture, block 984, need to make a decision        about whether continued efforts to resuscitate the victim are to        be terminated, block 948B. (See below, Section 5.5.5.4 regarding        pacing termination and see above, Section 5.5.2 for the        analogous situation with treatment-refractory ventricular        fibrillation.)

5.5.5.3 External Pacing Is in Progress; MP Decision Whether to CheckUnderlying Rhythm

If external pacing was in progress at the time of entry into theBradycardia/Pacing Protocol, block 977 leads to block 979, at whichpoint the MP has three options:

a) He can continue external pacing, in which case block 979 leads toblock 924D, and a return to the First Tier Arrhythmia Triage Protocol.

b) He may decide to briefly interrupt pacing or slow the pacing rate, inorder to assess the underlying rhythm (see, for example, Table 11, Time2:57). If the result, block 985, is that the victim is found to have asatisfactory underlying rhythm, external pacing is not restarted, andthe protocol returns, via block 924E, to the First Tier ArrhythmiaTriage Protocol. If the result is that the rate is inadequate to supportthe victim, the MP decides, block 986, between (i) resumption of pacing,block 924F, and (ii) if resuscitation is deemed futile, cessation ofpacing, block 948B.

c) He may find that pacing, though it results in electrical activationof the heart, fails to generate any significant mechanical activity(i.e. cardiac output/blood pressure). If the MP has exhausted allpossible means of achieving the restoration of mechanical function, andneither medical nor emergency personnel are on-scene nor are theyexpected to arrive on scene, the MP may need to make a decision toterminate resuscitation, block 948B.

5.5.5.4 MP Considerations Concerning Termination of Pacing

There are instances when bradycardia pacing may be futile.

a) Attempted pacing of the heart may fail to result in any cardiacelectrical activity. This might be the case, for example, in a victimwho was discovered too late to be able to be resuscitated.

b) Pacing of the heart may result in cardiac electrical activity butfail to result in significant mechanical activity, so called“electro-mechanical dissociation.” This might be the case in a victimwho has had a pulmonary embolus (a blood clot which lodges in thelungs), or after a myocardial infarction (heart attack) involving theloss of function of a large segment of the heart muscle.

In order for an MP to consider the termination of pacing, one or more ofthe following factors would be likely to be addressed:

a) the performance of CPR; It is possible that pacing may becomeeffective after the performance of CPR. In a preferred embodiment of theinvention the MP has various means for causing the performance of CPRincluding instructing the enabler and/or the use of a device whichautomatically performs CPR;

b) changes related to the electrode pad; These may include:

-   -   (i) removing the pad and re-applying the same one or a similar        one, in a different position;    -   (ii) removing the pad and re-applying a different one, in the        same, or in a different position; or    -   (iii) adding one or more additional electrode pads—e.g. to the        victim's back or left side (while keeping the original electrode        pad in place);

c) the duration of the resuscitation effort (The longer theresuscitation goes on without the restoration of adequate circulatorystatus, the less likely it is to ever achieve a satisfactory outcome.);

d) the proximity of the nearest emergency medical personnel;

e) the previously documented wishes of the victim, if such wishes areavailable to the MP; and,

f) local and federal statute.

The MP is much better qualified to address the aforementioned issuesthan an enabler using an AED would be. These aforementioned sixconsiderations apply to the suspension of resuscitation effort in theevent of refractory VF (Section 5.5.2, above).

5.6 Command Confirmation

Command confirmation is a fundamental part of the remote management of ahighly critical situation. In order for remote management to bepractical, the MP know with certainty whether each of his commands wasproperly executed. The system of confirmation signals is intended to dothis, as well as to identify not only the presence of a system fault butits location.

Command confirmation is illustrated and discussed:

a) in handshake section 5.2, in connection with FIGS. 14D through 14G;

b) in screen section 6.7, in connection with FIG. 44; and

c) in hardware sections 7.6, 7.7, 7.8 and 7.9, in connection with FIGS.51A through 54.

FIG. 24 is a flow diagram which illustrates the command confirmationroutine. Each command will generate four confirmation signals 1007B,1010B, 1014B and 1018B if it properly traverses the system and isexecuted. A failure at some point in the system, either in thetransmission of the command to its target in the PU, or in thetransmission of information back to the CS, will result in thegeneration of an error signal, viewed on the CS display console.

A command, block 1000, is encoded 1001 in the CS and then decoded 1005in the CS. If, block 1006, the decoded command matches the initial one,the receipt of confirmation signal #1 is displayed 1007B; if not, errorsignal #1 1007A is displayed. This is illustrated in FIG. 14D.

Confirmation signal #2 is generated when there is evidence that thecommand has been properly transmitted from the CS. FIG. 49 illustrateshow this occurs. The transmitted command 1002 is received, block 1008.If, block 1009, the command is properly received, the receipt ofconfirmation signal #2 is displayed 1010B; if not, error signal #2 1010Ais displayed. This is illustrated in FIG. 14E.

When the PU receives a command, block 1003, it retransmits, block 1011 a“copy” of it back to the CS as confirmation signal #3. If, block 1013,the CS receives the copy, the receipt of confirmation signal #3 isdisplayed 1014B; if not, error signal #3 1014A is displayed. This isillustrated in FIG. 14F.

When the PU executes the command, block 1004, it transmits, block 1015,a confirmation signal indicating the execution. If, block 1017, theconfirmation signal is received, the receipt of confirmation signal #4is displayed 1018B; if not, error signal #4 1018A is displayed. This isillustrated in FIG. 14G.

6. Central Station Screens 6.1 Basic Communication Screens 6.1.1Communication Status and Master Control Screen

FIG. 25 shows the Communication Status and Master Control Screen.

The top portion of the screen is a graphic display of signal quality atthe CS, the SU and the PU. Boxes 1101 can be colored green or red toindicate acceptable or unacceptable signal quality. Alternatively, morecolors or a numeric format may be used to supply more detailedinformation. This information may be used in three ways:

a) Although the communication system would ordinarily optimizecommunication routing and each of the appropriate transmitter andreceiver parameters, the MP is given the option to make his own choicesin this regard (see below).

b) The MP may be aided in the decision about whether to select analternate communication modality (i.e. screen text messages rather thanspeaking to the enabler, or having the enabler make touch sensitiveresponses rather than having the MP listening to the enabler) by thedisplay of signal quality.

c) The MP may decide that communication is so marginal that he wishes tomake use of the backup AED function of the portable unit.

The lower portion of the screen:

a) gives the MP access to selecting or overriding system choices forcommunication parameters and features;

b) gives the MP access to alternative communication modalities; and

c) allows the MP to select the state of the master control unit.

Touch sensitive button 1102 allows the MP to change any aspect of the CSprocessing input (referred to as options 1A in Table 20 and shownschematically as block 506 in FIG. 14A) and/or any aspect of the CScommunications output (referred to as options 1B and represented asblock 508 in FIG. 14A). In a preferred embodiment of the invention,touching 1102 brings up a menu of options (not shown) which may overlayscreen 1100, split the screen, or appear on another screen.

Touch sensitive button 1104 allows the MP to change any aspect of PUcommunications input (referred to as options 3A in Table 20 and shownschematically as block 512 in FIG. 14A) and/or any aspect of the PUprocessing output (options 3B and block 514 in FIG. 14A). Touchsensitive sub-menus (not shown) allow these selections.

Touch sensitive button 1110 allows the MP to change any aspect of PUprocessing input (options 6A and block 519 in FIG. 14A) and/or anyaspect of the PU communications output (options 6B and block 521 in FIG.14A).

Touch sensitive button 1108 allows the MP to change any aspect of CScommunications input (options 8A and block 525 [FIG. 14A]) and/or anyaspect of the CS processing output (options 3B and block 527).

In the preferred embodiment of the invention, in which a stationary unitlinks the PU and the CS, modifications are possible in the input andoutput characteristics of the SU, a menu for which is accessed bytouching 1103. This allows the MP to modify SU input from the CS, SUoutput to the PU, SU input from the PU and SU output to the CS. The MPmay also modify the communication path between the CS and the PU(options 2 and 7 in Table 20 and blocks 510 and 523 in FIG. 14A) byhaving access to communications routing. If a SU is interposed betweenthe PU and the CS, the number of routing options increases.

If, despite attempts by the system or the active efforts of the MP, itis not possible to maintain satisfactory voice communication, the MP hasthe option of using text messages in either (or both) sides of hiscommunication with the enabler (see discussion of FIG. 15). By touching1105, he can change the enabler input to a touch sensitive screenmethod, his own input to text messages for the enabler, or both. He canselect voice prompts (see below) by touching 1111, which takes him tothe Voice Prompt Screen shown in FIG. 26.

After a satisfactory data-commands handshake, the MP takes control ofthe PU by touching 1106 which sends a command to the master control unitin the PU to set MC=1 (see FIGS. 140, 48, 51A and 54). If communicationis interrupted, the PU automatically reverts to MC=2, i.e. AED control.There may also be other circumstances where the MP wishes to voluntarilyset MC=2; One example is a communication degradation after setting MC=1,that is not severe enough to automatically set MC=2 but which the MPdeems to result in his inability to satisfactorily control thesituation. In such a circumstance, the MP touches “GO TO AED CONTROL”1107. Transmission of this command is similar to that of MC=1, in termsof the hardware involved. If at some later time after sending “GO TO AEDCONTROL” communications improve, the MP may again touch “GO TO MPCONTROL” to reset MC=1.

Upon the arrival of qualified emergency medical personnel, the EMT, theMP can hand control over by touching “GO TO EMT CONTROL” 1112. Thissends a command to set MC=3, allowing the EMT to use the PU as the MPuses it.

At the conclusion of a procedure the MP sends a command to return the PUto its standby state by touching “END SESSION” 1113. This sends acommand to set MC=0.

If the MP wishes to do a diagnostic check of the PU-SU system, he callsup the MP Directed Portable Unit Diagnostic Check and Maintenance Screen(see Section 6.4 and FIG. 41) which allows him to set MC=4 and performthe check. He can access that screen by entering “CONTROL M” on thekeyboard, which brings up the Main Screen Menu 1600, on which he selects“PU CHECK AND MAINTENANCE” (see Section 6.6 and FIG. 43).

6.1.2 Voice Prompt Screen

The MP may choose to use voice prompts in the event of communicationdifficulties. He may also make this choice in the case of a foreignlanguage speaking MP, if an interpreter is not available.

FIG. 26 shows screen 1115 which provides the MP with access to anextensive menu of voice prompts (see Appendix 1) and methodology fortheir selection and delivery.

Since there are many situations which may occur during a cardiac arrestor emergency, the list of possible voice prompts is necessarily long. Tofacilitate the MP's selection among the possible voice prompts, the menuhas been divided into nine sub-menus:

a) the “INTRODUCTORY STATEMENTS MENU”, block 1120;

b) the “EVENT DESCRIPTION MENU”, block 1121;

c) the “LOCK RELEASE MENU”, block 1122;

d) the “TRIP TO VICTIM MENU”, block 1123;

e) the “ON ARRIVAL MENU”, block 1124;

f) the “ATTACH PADS AND PERIPHERALS MENU”, block 1125;

g) the “SHOCK/PACE MENU”, block 1126;

h) the “MISCELLANEOUS MENU”, block 1127 and

i) the “SWITCH TO AED MENU,” block 1128.

Some of the sub-menus have only a few choices (e.g. seven for theSHOCK/PACE menu) while others are longer. The ATTACH PADS ANDPERIPHERALS MENU has one hundred choices—of necessity a large numberbecause a) these acts involve one of the portions of the resuscitationprocedure where enabler participation is mandatory, and b) correctperformance by the enabler will increase the chance of a successfulresuscitation.

In order to allow the MP to rapidly scan the menu items, they arepresented on the screen-in screen 1116, once the MP touches one of1120-1128 and selects a sub-menu. He can use the scroll bar on the rightof the screen, the arrow keys on the keyboard and the mouse to rapidlyscan the list. Once he finds an appropriate choice, he can deliver it bytouching 1118. Methods for streamlining selection include a) shorteningthe menu and b) allowing the MP to select a choice by entering the firstword or a key word on the keyboard.

If the MP wishes to increase or decrease the volume at the PU at whichthe prompt is delivered, he can do so using 1117B or 1117A.

6.2 Portable Unit Setup Screens 6.2.1 Portable Unit Deployment Screen

The MP will release the PU from its locked state after:

a) satisfactory communication with the enabler is confirmed (FIG. 15);

b) the MP confirms that he is or is may be dealing with a cardiacemergency (FIG. 16A, block 779); and

c) the MP confirms that the enabler is willing to help (FIG. 16A, block781).

When these conditions are met (block 782), the MP a) calls the 9-1-1which corresponds to the PU location and b) releases the PU.

Screen 1135 displays the PU location in block 1136, and the telephonenumber of the 9-1-1 nearest the victim, in block 1137A, both items ofinformation having been obtained at the time of the data-commandshandshake. The MP summons the emergency medical team by touching 1137B.If their estimated arrival time is known, it can be displayed in block1140.

To release the PU, the MP touches 1141 on the PU Deployment Screen 1135,shown in FIG. 27. When the electromagnetic lock successfully opens,releasing the PU from the SU, the PU transmits a telemetry signal to theCS (block 793, FIG. 16B) which is shown in block 1142, on screen 1135.It is also registered on the Event Log (see below, FIG. 44). In theevent of a failure of the lock to release the PU, the MP may observe afailure signal, block 1143. He can override the electromagneticapparatus with a mechanical release 184B (FIG. 8) that can be performedby the enabler after entering the proper alphanumeric combination to thethe lock 184A (FIG. 8). The MP tells the enabler the correctcombination, after viewing it, block 1144. (It may be provided duringthe data-commands handshake.)

The PU is separated from the SU upon instruction by the MP (block 807,FIG. 16C), at which point the MP a separation signal is generated, anddisplayed in block 1145, and the Event Log. After enabler transportationof the unit to the victim, and proper placement on the ground, elements178 (FIG. 8) cause the generation of a portable unit touchdown signal(block 829, FIG. 18A) which is displayed on the PU Deployment Screen,block 1146.

Once the PU is on the ground next to the victim, the MP deploys thevideo boom 112 (FIG. 6B, and block 830 of FIG. 18A) while speaking tothe enabler and quickly re-establishing that audio contact is good(block 834 of FIG. 18B). The bottom of the PU Deployment Screen allowsthe MP to go to either:

a) the Communication and Master Control Screen, FIG. 25, if audiocommunication needs refinement, by touching 1147;

b) the Video Control and Instruction Screen, FIG. 28, by touching 1148;or

c) the Initial ECG Screen, FIG. 29, by touching 1149.

The start time and elapsed time of the event are displayed in blocks1138 and 1139 of screen 1135.

6.2.2 The Video Control and Instruction Screen

This screen, 1160, allows the MP to:

a) manipulate the video boom;

b) adjust viewing parameters for what he sees;

c) provide instructional material for the enabler; and

d) determine the format and mode of operation of the PU screens 156.

The controls at the upper right hand portion of screen 1160 allows theMP to manipulate the video boom, and thereby get a better view of thevictim and ECG pad application. In a preferred embodiment of theinvention, the video boom has one or more angulations along its shaft,which can be controlled (like a medical endoscope) by the MP. Thejoystick (see FIGS. 3 and 49) facilitates control of the boom vector.The length of the boom is also controllable. Controls for focus, zoom,brightness and contrast are available. Depending on bandwidthavailability, the MP may wish to adjust the frame rate for his own orfor the enabler's video.

Victim clothing removal is facilitated by having the MP indicate whatarea specifically must be exposed. Electrode pad application isfacilitated by showing either a cartoon representation of the victim (bytouching 1163) or by showing the actual victim (by touching 1162) andthen superimposing either a cartoon of a properly placed electrode pad,an image of an actual in proper position, or markings on the videoscreen which indicate proper placement (see block 879, FIG. 18E). Thecomposite image is shown on one of the PU screens, and onscreen-in-screen 1161. Markings to indicate proper pad placement may begenerated by touching 1164 and then touching the appropriate spot on1161, or using the mouse or joystick to accomplish this. If the MPwishes to display a superimposition of the actual electrode pad, heselects the choice of electrode pad among the six touch sensitive blocks1166. (Once the pad backing is removed, the system “knows” which pad hasbeen selected. However, backing removal should occur not occur untilafter the beginning of the pad placement instructions.) When the MP hasselected his pad choice, he tells the enabler which shelf in thetool-kit (FIG. 7A) to get it from, and touches “SHOW” 1167. If the MPchanges his selection, he touches “CANCEL 1168” and is then at libertyto make another selection. After successful pad application, the MPtouches “INITIAL ECG SCREEN” 1169 which takes him to screen 1180 for ECGsetup (see Section 6.2.3).

The lower right hand portion of screen 1160 allows the MP to select theformat of each of the PU screens 156. Their content is displayed on1171A and 1171B.

If the enabler can not properly hear the MP after PU placement at thevictim side, and if this condition is not remedied by any of the audiooptions available, the MP may select to use text messages for hisinstructions to the enabler. He does so by touching 1174 and thentouching either 1172A or 1172B to select the particular PU screen hewould like to allocate for such messages. He can facilitate enablerviewing of these messages using the available controls for brightness,contrast and font size. If the MP cannot properly hear the enabler, andcannot remedy the situation, he can ask the enabler to use a touchsensitive yes/no (or multiple choice) format to answer MP questions,block 1177, or ask his own questions (using a virtual, touch sensitivekeyboard), block 1178. The MP can place these formats on each PU screenby touching one of 1177 and 1178 and then touching one of 1172A and1172B. The MP can determine which screen is allocated for pad placement(including the choice of both) using 1175 and 1176, and can show animage of himself (which may be reassuring to the enabler) by selecting1179. If the MP wishes to display more than two items, he can use ascreen-in-screen format by touching 1173.

6.2.3 Initial ECG Screen

Once the electrode pad is in place, the MP optimizes hiselectrocardiogram recording, if necesssary, using the Initial ECG Screen1180 shown in FIG. 29.

The presence of multiple electrodes on some of the available choices forECG pad means that the MP will have choices for ECG lead selection thatwould not be available if only two electrode pads were in use. The ECGis displayed on the upper portion of the screen with touch sensitivegain controls to the right of each displayed lead. The name of the ECGlead whose vector orientation most closely resembles that of the eachtracing displayed to its left. If the MP wishes to view other ECG leads,he can replace the three lower tracings with alternate choices bytouching 1186. If he wishes to view a previous group of three he selects1187. A unipolar measurement of the impedance of each pad (as a measureof how well it is contacting the victim's chest) is displayed in screen1184. Each pad may be:

a) shown in green or red, as a “go-no go” classification;

b) shown in a format with more than two colors and an equal number ofpossible classifications; and/or

c) shown associated with a number (indicated as “uu”, “vv”, “xx”, “yy”and “zz” in FIG. 29).

Based on what he sees, the MP will want to go from screen 1180 toeither:

a) the appropriate pad setup screen (FIGS. 30-32), by touching 1188, ifhe wishes to select non-standard choices of electrode recording formatBy this time, the system will know which pad he has selected since thepad backing would have been removed. He therefore need not specify whichof the three electrode pad setup screens he needs;

b) the Main Pacing Screen, by touching 1190;

c) the Main Defibrillation Screen by touching 1192; or

d) the Anti-Tachycardia Pacing Screen by touching 1194.

Elements 1182 are for use during pacing adjustment (see below).

6.3 Arrhythmia Management Screens

FIGS. 30-40 show examples of possible arrhythmia management screenconfigurations. These examples do not constitute unique configurations.Other embodiments are possible, including:

a) embodiments with two or more of the individually shown screens mergedinto one;

b) embodiments with one of the individually shown screens divided intotwo or more screens;

c) embodiments in which there are a larger or a smaller number ofchoices for the value of a particular parameter (e.g. the value ofdefibrillation energy, FIG. 34) available for the MP to select;

d) embodiments in which there are one or more different choices for thevalue of a particular parameter (e.g. 75 joules for the value ofdefibrillation energy, FIG. 34) available for the medical professionalto select;

e) embodiments in which one or more of the parameters shown asselectable by the MP, may be either selected by an algorithm outside thecontrol of the MP, or may be fixed (e.g. pulse shape);

f) embodiments in which one or more features of arrhythmia control arenot utilized (e.g. anti-tachycardia pacing, FIG. 37);

g) embodiments in which the storage and display of previously usedparameter values (e.g. “SHOW PREVIOUS”, element 1202A, FIG. 33) iseither formatted differently, or not available to the MP; and

h) embodiments in which there either are a larger number, or a smallernumber of commands leading to therapy delivery (e.g. the three commandsequence: “SELECT PREVIOUS”, element 1202A; “ACCEPT”, element 1206; and“DELIVER”, element 1208 [all in FIG. 33]).

6.3.1 Defibrillation Management Screens

FIG. 33 shows the Main Defibrillation Screen 1200. The buttons on it,(touch sensitive, light sensitive, actual depressable buttons, keyboardor voice entries) allow the MP to select defibrillation parameters, anddeliver a shock.

In the embodiment which corresponds to FIGS. 30-36, selection ofdefibrillation parameters will consist of either using default values(which requires only Main Defibrillation Screen 1200) or will requirethe accessing of one or more other screens for the selection of:

a) non-default values of defibrillation energy (FIG. 34); and/or,

b) non-default values of pulse synchronization (FIG. 35); and/or,

c) non-default values of pulse shape (FIG. 36); and/or,

d) non-default values of electrode configuration (FIGS. 30-32).

6.3.1.1 Paths to Main Defibrillation Screen

The MP 301 ordinarily first reaches the Main Defibrillation Screen fromthe Initial ECG Screen (FIG. 29), upon MP's recognition that the victimis in either ventricular fibrillation or shock-requiring ventriculartachycardia. Other routes by which the MP would arrive at the MainDefibrillation Screen are:

a) from any of the aforementioned screens (FIGS. 30-32 and 34-36) usedfor specifying non-default values of defibrillation parameters;

b) from the Anti-Tachycardia Pacing Parameters Screen (FIG. 37);

c) from the Main Pacing Screen (FIG. 38); and,

d) from the Screen Menu (FIG. 43).

6.3.1.2 Method of Operation: Defibrillation Screens 6.3.1.2.1 DefaultValues: Main Defibrillation Screen

If the MP decides to defibrillate using default values, he:

a) selects “ALL DEFAULT VALUES” 1210;

b) touches “ACCEPT” 1206;

c) waits for the confirmation signal from the PU that charging has beencompleted;

d) confirms the persistence of a shock-requiring rhythm; and,

e) touches “DELIVER” 1208.

This causes the PU to deliver an asynchronous shock via the defaultelectrode configuration, with the default parameters of energy and pulseshape. (This was the case for the initial shock during the samplecardiac arrest described in Table 11, Time: 2:20-2:25.)

Typical default values are:

a) Energy=maximal;

b) Synchronization=off;

c) Waveform=biphasic; and,

d) Electrodes=α and δ (when using the five electrode pad).

The actual default values may be set in a number of ways:

a) They may be programmed in a way such that, once initially set, nouser of the system has access to them;

b) They may be programmed such that MPs do not have access, but suchthat certain members of the staff do have access; or

c) They may be programmed so that MPs have access, for example, via apassword.

As indicated in the sample cardiac arrest section, touching “ACCEPT” onthe Main Defibrillation Screen results in the transmission of a commandfrom the central station to the portable unit to begin charging its highvoltage capacitors in preparation for shock delivery. Touching “DELIVER”results in the transmission of a command to deliver the programmedenergy and waveform via the programmed combination of electrodes, ineither a synchronized or asynchronous fashion, as programmed. If thetachycardia or fibrillation were to terminate in the few seconds betweenthe MP's touching of “ACCEPT” and the completion of capacitor charging,the MP would touch “ABORT DEFIB” 1209, which would send a command to thePU to discharge its capacitors internally (i.e. not through the victim).The MP would also select “ABORT DEFIB” if the tachycardia orfibrillation changed to a rhythm which might respond to anti-tachycardiapacing (see Section 6.3.2, below).

6.3.1.2.2 Non-Default Values

Instead of selecting “ALL DEFAULT VALUES” for the defibrillationparameters, the MP may select one or more non-default values. Anon-default value is selected by touching 1212B (non-default energy),1214B (for synchronized energy delivery, i.e. the non-default approach),1216B (non-default waveform) or 1218B (non-default electrodeconfiguration). Each of the non-default buttons 1212B, 1214B, 1216B and1218B leads to a different defibrillation detail screen (1230, 1240,1260, 1290, 1310 and 1340) which contains a menu which lists possiblenon-default settings.

Each of the aforementioned defibrillation detail screens, when selected,may be displayed in a variety of ways:

a) A detail screen may overlay 1200, the Main Defibrillation Screen.Once the MP selects the appropriate value on the defibrillation detailscreen, the detail screen disappears, and the main defibrillation screen(no longer covered by the detail screen) is again visible.

b) Selecting a defibrillation detail screen may cause it to appear on asecond MP work screen (e.g. central station monitor 332, FIG. 3), withthe Main Defibrillation Screen 1200 remaining visible on a first MP workscreen (e.g. central station monitor 330, FIG. 3).

c) Selecting a defibrillation detail screen may cause it to split thescreen such that one half is the main defibrillation screen, and theother half is the defibrillation detail screen.

d) Selecting a defibrillation detail screen may cause it to become a“screen-in-screen” with the inner screen being the detail and the outerscreen being the Main Defibrillation Screen 1200.

Once the MP has selected a non-default value and has then returned tothe Main Defibrillation Screen, he may either a) select default valuesfor the other defibrillation parameters, or b) select other non-defaultvalues for one or more of the remaining parameters.

To select a default value for one of the defibrillation parameters, theMP touches the appropriate one of buttons 1212A (default energy, themaximum value), 1214A (synchronization off), 1216A (default waveform,biphasic) or 1218A (default electrode pattern). An example of thisapproach is presented in Section 4.2 which describes an hypotheticalcardiac arrest (see Table 11, Time 2:31-2:33: After selectingnon-default values for the defibrillating electrodes, the MP selectsdefault values for each of the other three parameters.)

Embodiments of the invention are possible in which non-selection of aparameter results in the selection of the default value.

Default selections that have been chosen by the medical professional arepreferably indicated on the Main Defibrillation Screen by eitherhighlighting, backlighting, coloring or otherwise visually emphasizingthe word within the button (1212A, 1214A, 1216A or 1218A) thatcorresponds to the selection.

Non-default selections that have been chosen by the MP are alsopreferably displayed on the Main Defibrillation Screen. One method ofdoing this would be as follows:

a) A non-default energy value, if selected, would be displayed as anumber within button 1212B, replacing the word “OTHER”.

b) Synchronization, if selected, would be indicated by eitherhighlighting, backlighting, coloring or otherwise visually emphasizingthe word “YES” within button 1214B.

c) A non-default pulse contour, if selected, would be displayed, alongwith the numerical parameters which specify it, in the Pulse ContourMiniscreen 1216C. This screen-within-screen would be similar oridentical to its counterpart element 1278 on the Pulse Shape Screen (seebelow, Section 6.3.1.2.2.3).

d) A non-default electrode pattern, if selected, would be displayed inMiniscreen 1218C. The content of this Miniscreen would show the patternof electrodes selected for energy delivery, in a manner similar oranalogous to the display in element 1322 (see below, Section6.3.1.2.2.4.2). With electrode pads other than the matrix electrode pad,those electrodes selected for energy delivery could be either (i)displayed in Miniscreen 1218C, or (ii) listed within button 1218B,replacing the word “OTHER”.

When all of the defibrillation parameters have been selected, the MP:

a) touches “ACCEPT” 1206;

b) waits for the confirmation signal from the PU that charging has beencompleted;

c) confirms the persistence of a shock-requiring rhythm; and,

d) touches “DELIVER” 1208.

This causes the PU to deliver a shock via the electrode configuration,and with the parameters that have been selected. If the MP wished toabort the shock after charging had begun, he would touch “ABORT DEFIB”1209.

The MP may, during the course of a resuscitation, need to shock a victimmore than once. In such a situation, the MP may wish to review theparameter choices selected for one or more previous shocks. Touching“SHOW PREVIOUS” 1202A results in the display of each of:

a) the energy,

b) synchronization,

c) electrode choice, and

d) the waveform

for the previous shock. The choices for these previously selectedparameters are displayed on the Main Defibrillation Screen in a mannersimilar or identical to that mentioned above, for the display of currentparameter selections, using the display capability of 1212A,B; 1214A,B;1216A-C and 1218A-C.

If, after touching “SHOW PREVIOUS”, the MP wishes to select all of thedisplayed parameters, he touches “ACCEPT” 906. If, after touching “SHOWPREVIOUS”, the MP wishes to select some but not all of the displayedparameters, he over-writes the parameters he wishes to change, and thentouches “ACCEPT”.

Touching “SHOW PREVIOUS” a second time, results in the display of theparameters used for the next previous shock, i.e. the shock before theimmediately preceding shock. Each successive time that “SHOW PREVIOUS”is touched, the parameter values for the next earlier shock aredisplayed. Any of these sets of displayed values may be selected (withor without modification, as indicated above,) by touching “ACCEPT” 906.

If the MP, using “SHOW PREVIOUS”, views two or more sets of previousvalues, and then wishes to “reverse direction”, i.e. to again view theparameter values of the next most recent shock, he touches “SHOW NEXT”1202B. Touching “SHOW NEXT” a second time, results in the display of theparameters used for the next most recent shock. Each successive timethat “SHOW NEXT” is touched, the parameter values for the next shock aredisplayed. Thus the MP may move either backwards (using “SHOW PREVIOUS”)or forwards (using “SHOW NEXT”) through the sequence of alreadydelivered shocks and review their parameters. Any of these sets ofparameters may be selected (with or without modification) by touching“ACCEPT” 906.

An alternate method of displaying sets of previously utilized parametersis for the MP to save desirable sets to memory. This is accomplished byhaving the MP touch “SAVE” 1204B. Later on (either during treatment ofthe same victim or alternatively during the treatment of another victim)the MP may retrieve these values by touching “SHOW SAVED” 1204A. If,after touching “SHOW SAVED”, the MP wishes to select all of thedisplayed parameters, he touches “ACCEPT” 1206. If, after touching “SHOWSAVED”, the MP wishes to select some but not all of the displayedparameters, he over-writes the parameters he wishes to change, and thentouches “ACCEPT”.

When more than one set of values is saved, the sets can be labelled invarious ways including:

a) having each saved event time-stamped, or time- and date-stamped;

b) numbering the saved events;

c) naming the saved events with a keyboard entry at the time the eventis saved; and,

d) combinations of the above.

When more than one event has been saved, touching “SHOW SAVED” 1204Aresults in the display of the list of saved sets of parameters and theappropriate identifier. The MP can then choose among them either bykeyboard entry or by viewing them on a touch sensitive screen, with theMP selecting the desired set by touch.

The method of displaying previously used sets of defibrillationparameters discussed hereinabove is not unique. One alternate methodshows previous parameter sets on-screen, without having to request theirdisplay. This is discussed below in Section 6.3.1.2.2.4 regarding theelectrode setup screens shown in FIGS. 30-32.

6.3.1.2.2.1 Defibrillation Energy Screen

If a less than maximal energy output is desired, the MP touches the“OTHER” button 1212B in the Energy section of the screen which wouldlead to the display of the Defibrillator Energy Screen 1230 (FIG. 34).This screen 1230 shows seven values of energy ranging from 5 joules tomaximal. (Although values at the low end would be impractical fordefibrillation, they could be used for the synchronized conversion ofventricular tachycardia or atrial flutter.) A particular value of energyis selected (in the case of a touch sensitive screen, for example) bytouching within the box corresponding to that value, followed bytouching within the box labelled “ACCEPT”. Touching one of the buttonswhich specifies the energy value results in highlighting, backlighting,coloring or otherwise visually emphasizing the number within the button.Touching “ACCEPT” returns the MP to the Main Defibrillation Screen.

If the MP changes his mind after touching a particular energy value, hemay over-write the previous choice by simply selecting another value. Onthe Defibrillation Energy Screen, this would result in visual emphasisof the new choice, and removal of visual emphasis of the over-writtenchoice.

An alternative embodiment would not have the “ACCEPT” button. In thisembodiment, the act of touching one of the buttons which delineate aparticular energy value would both select that value and return the MPto the Main Defibrillation Screen.

If the MP desired an energy value that was not among the screen choices,he could touch “OTHER” 1234 and then enter the value via the keyboard;The value would be displayed on the defibrillation energy screen inbutton 1234, replacing the word “OTHER”. The MP would then touch“ACCEPT” 1232 on the Defibrillation Energy Screen (or press “Enter” onthe Keyboard).

6.3.1.2.2.2 Synchronization Screen

During ventricular fibrillation, the ECG waveform is aperiodic and theMP will want to use an asynchronous shock. For certain cases ofventricular tachycardia, however, the MP may desire a shock which issynchronized to a particular moment of the “R-wave” of the ECG waveform.With an R-wave synchronized shock, a lower (and sometimes much lower)amount of energy may be used for termination of tachycardia. This wouldbe advantageous in a conscious, a semi-conscious or a very large victim.

An R-wave synchronized shock is also necessary if a shock is being usedto treat atrial fibrillation, supraventricular tachycardia oratrioventricular reciprocating tachycardia. Although these latter threetachycardias are not as directly life-threatening as ventriculartachycardia of ventricular fibrillation, at times they do pose a majorthreat to a victim's safety. Therefore, an MP may encounter a victim whois unconscious or severely compromised as a result of one of theserhythms, and accordingly may deem it appropriate to use a synchronizedshock to terminate the tachycardia.

Care must be taken to avoid mistakenly delivering the shock on the“T-wave;” T-wave shocks may actually precipitate ventricularfibrillation. Circuitry for automatically selecting the peak of theR-wave as the desired moment for energy delivery is known in the art. Inclinical practice a manually operated defibrillator, when operated inthe synchronous mode, displays its assessment of the R-wave peak, sothat the operator may confirm that synchronization is proper, prior toenergy delivery.

In a preferred embodiment of the invention, when desiring to deliver anR-wave synchronous shock, the MP will assure that the timing of theshock is indeed synchronous with the R-wave of the ECG. This is done byfirst selecting “YES” 1214B on the Main Defibrillation Screen, whichresults in the display of the Synchronization Screen 1240, shown in FIG.35. The victim's ECG is displayed in window 1242 of screen 1240, with avertical cursor (or other on-screen indicator) 1244 marking the momentof maximal R wave amplitude as determined by the central station-basedalgorithm. The cursor may mark one or all of the displayed beats. If theMP feels that the cursor does, in fact, mark the point of the R-wavepeak, he touches “ACCEPT” 1254 which returns him to the MainDefibrillation Screen, where he can go on to choose any shock parameterswhich have not yet been specified.

If the MP feels that the cursor has not been properly placed, he hasthree options:

a) He can observe a determination of the R-wave peak by a portable unitalgorithm;

b) He can manually select his own synchronization timing; or,

c) He can abandon synchronization and return to asynchronous energydelivery.

The MP can select any of these choices by touching 1248, 1250 or 1252respectively, on the top portion of screen 1240.

The first of the aforementioned three choices is the use of thePU-determined R-wave peak. The MP can, in a preferred embodiment,display the selection of the R-wave peak by circuitry within the PU.(The PU selection will not necessarily be identical to the R wave peakselected by a central station algorithm, if transmission of the PU ECGsignal resulted in distortion of the signal.) The MP displays thePU-selected R wave peak by touching “SHOW PORTABLE UNIT AUTO-SYNCH”1248. If he agrees with it, he touches “ACCEPT” 1254, and returns to theMain Defibrillation Screen. If he wishes to again view the R-wave peakselection based on the central station signal, he touches 1246 “SHOWCENTRAL STATION AUTO-SYNCH”.

The second choice of the aforementioned three choices is manualselection of synchronization timing. By touching the “MANUAL” button1250, the MP enables buttons 1256A and 1256B which allow him to move thecursor to the right or left on ECG display 1242. Such movement may beaccomplished by either:

a) continuously touching one of the buttons, resulting in movement ofthe cursor at a constant rate;

b) repeatedly touching the button, resulting in movement of the cursorby a fixed amount per touch; or,

c) a combination of a) and b).

When the cursor reaches the desired position, the MP touches “ACCEPT”1254 which returns him to the Main Defibrillation Screen.

Screen 1240 shows additional means of enhancing the peak of R-waveselection process. The degree of amplification of the ECG signal displaymay be adjusted up or down using gain control buttons 1258A and 1258B.At the bottom of screen 1240, there are 12 buttons which allow forselecting different ECG leads for display. This allows the MP to avoid alead choice in which the T-wave amplitude is not significantly smallerthan the R-wave amplitude. Depending on the electrode pad being used,one or more lead choices may not be available.

If the MP decides to abandon synchronization, either a) because ofuncertainty in distinguishing R-waves from T-waves (as is occasionallythe case whether the distinction is operator or algorithm-based), or b)because the rhythm may have deteriorated in the moments after thedecision was made to attempt a synchronized energy delivery, the MPtouches “ASYNCH” 1252, followed by “ACCEPT” 1254, and is returned to theMain Defibrillation Screen.

6.3.1.2.2.3 Pulse Shape Screen

A preferred embodiment of the invention, allows the MP to select thedetails of the defibrillation pulse contour. If the MP desires to use adefibrillation waveform other than a pre-specified biphasic waveform, hetouches “OTHER” 1216B on the Main Defibrillation Screen, which takes himto Pulse Shape Screen 1260, FIG. 36.

This screen allows for the MP three groups of options:

a) the delivery of a monophasic defibrillation pulse;

b) the delivery of a biphasic pulse whose shape is other than thedefault; and,

c) the delivery of a waveform which is more complex than the defaultbiphasic pulse.

The MP can select a monophasic pulse by touching “MONOPHASIC” 1262. Hewould then either utilize a default value of pulse width by selecting“ACCEPT” 1270, or would specify a particular pulse width value by:

a) touching “PULSE WIDTH” 1268;

b) next, using the keyboard to input a numerical value for the pulsewidth; and then

c) touching “ACCEPT” 1270 on Pulse Shape Screen 1260, which returns himto the Main Defibrillation Screen.

The MP can tailor the shape of the default biphasic pulse by using the“LEADING P.W.” button 1272A to specify the width of the first phase, andusing the “TRAILING P.W.” button 1272B to specify the width of thesecond phase. Each of buttons 1272A and 1272B is used in a manneranalogous to that of button 1268: that is, after touching each one, theMP inputs a pulse width value via the keyboard. After the two values ofwidth have been inputted, touching “ACCEPT” 1270, returns the MP toscreen 1200, and allows for the delivery of the specified biphasicpulse, once energy, synchronization and route are specified.

The delivery of a waveform with three or more phases is selected bytouching “OTHER” 1266, on screen 1260. The width of the first phase isthen specified by touching “I” 1276A, and then entering its value viathe keyboard. Similarly the width of the second phase is specified bytouching “II” 1276B, and then entering its value via the keyboard. Thethird phase is specified by touching “III” 1276C and then specifying itswidth. If a fourth phase is desired, the MP touches “ADDITIONAL” 1276Dand using the keyboard to input information about each additional phase.

In a preferred embodiment of the invention, the MP's choice of thenumber of phases in the defibrillation pulse would be displayed byvisually emphasizing the word in the selected button. For example, theword “MONOPHASIC” would be highlighted after button 1262 is touched.Numeric selections would be displayed by inserting the appropriatenumeric value into the corresponding button. For example, the number“6.0”, if selected for the width of the leading component of a biphasicpulse, would appear inside of button 1272A, beneath the words “LEADINGP.W.”.

As is the case with other screens, the MP has the option of changing analready specified parameter choice by “over-writing it,” i.e. byselecting a new choice. For example, if the MP brought up Pulse ShapeScreen 1260 initially intending to select a monophasic pulse, thenselected the monophasic pulse by touching “MONOPHASIC” 1262, and thenchanged his mind, and wanted a biphasic pulse he could either a) touch“DEFAULT” 1274 which would select the default biphasic waveform, or b)touch “BIPHASIC” 1264, after which he would need to input the values ofleading and trailing pulse width, as described above, to select abiphasic pulse with a width differing from the default setting. Changinga previously selected choice of phase number results in visual emphasisof the word inside the button corresponding to the new choice andremoval of the emphasis on the no longer selected choice. The display ofnumeric values is also adjusted to reflect a change of choice.

If the MP has already touched “ACCEPT” 1270 and thereby returned to theMain Defibrillation Screen 1200, he still has the option of changing hiswaveform choice, as long as he has not delivered the shock. He would doso by again touching “OTHER” 1216B on screen 900, which would return himto Pulse Shape Screen 1260, after which he can over-write his previouschoice.

The method of specifying pulse shape described herein is not unique.Multiple other approaches are possible including:

a) allocating more or all information inputting to the keyboard;

b) using different arrangements of buttons to specify the pulse contour(for example, the function of pulse width specification using buttons1268, 1272A, 1272B, 1276A, 1276B, 1276C and 1276D could be accomplishedusing a smaller number of buttons);

c) specifying “tilt” (a measure of the rate of decline in voltage duringthe pulse) rather than (or in addition to) pulse width, and/or,

d) specifying other descriptors of pulse shape including the maximumand/or minimum amplitude of each phase, delays between phases, and thewaveform contour details—if other than the classic truncatedexponential;

e) using a “library” of pre-stored pulse shapes.

Pulse Contour Miniscreen 1278 allows the MP to have an image of thepulse that he “constructs,” using the options available on the pulseshape screen. The Miniscreen may also display the numerical values foreach parameter which specifies the selected shape.

The MP may call up previous choices of parameter values for the PulseShape Screen by touching buttons analogous to those on the MainDefibrillation Screen. In particular:

a) “SHOW PREVIOUS” 1280A on screen 1260 is analogous in function to“SHOW PREVIOUS” 1202A on screen 1200;

b) “SHOW NEXT” 1280B on screen 1260 is analogous in function to “SHOWNEXT” 1202B on screen 1200;

c) “SHOW SAVED” 1282A on screen 1260 is analogous in function to “SHOWSAVED” 1204A on screen 1200; and,

d) “SAVE” 1282B on screen 1260 is analogous in function to “SAVE” 1204Bon screen 1200.

“SHOW PREVIOUS”, “SHOW NEXT” and “SHOW SAVED” parameters are displayedin the same way that current selections are. The MP may accept a savedset of waveform parameters “as is” or modify some of the waveformparameters by over-writing and then accept, as per the discussion inSection 6.3.1.2.2.

Since the MP may also use the Pulse Shape Screen to specify the shape ofa pacing pulse (see below), and since the shape of the pacing pulse maybe different from that of the defibrillating pulse, means are providedfor indicating which of the two pulse types is being specified. Thedefault pulse assignment (i.e. defibrillation vs. pacing) is based onthe immediately prior screen used by the MP: If the prior screen was theMain Defibrillation Screen, then the default arrangement is for screen1260 to specify the shape of the defibrillation pulse. If the priorscreen was the Main Pacing Screen 1370 (see text below and FIG. 38),then the default arrangement is for screen 1260 to specify the shape ofthe pacing pulse. One of buttons 1284 (“DEFIB PULSE”) and 1286 (“PACINGPULSE”) is highlighted or visually emphasized at all times, indicatingwhich of the two types of pulses is being selected. Should the MP wishto specify the other pulse type, he does so by first touching thenon-highlighted of the two buttons, and then selecting the desiredspecifications for the alternate pulse. (Touching “ACCEPT” next takesthe MP a) to the Main Pacing Screen 1370 if he had just specified thepacing pulse shape parameters, or b) to the Main Defibrillation Screen1200 if he had just specified the defibrillation pulse shapeparameters.)

6.3.1.2.2.4 Electrode Setup Screens

The MP may decide to use non-default values of defibrillating electrodechoice if:

a) a prior defibrillation attempt with the default electrode choice wasunsuccessful;

b) the patient is large;

c) the patient is small;

d) a high impedance value indicates that the either one or moreelectrodes is making poor contact with the victim, or there is a damagedpad wire; or,

e) the MP sees (via the video camera) that the pad was attached to thevictim with either an improper position or orientation.

In a preferred embodiment of the invention the tearing of conductivestrip 266 (FIG. 5E) at the time of pad application would have alreadyinformed the system which type of electrode pad(s) (five electrode vs.matrix pad vs. single electrodes) has been applied to the victim(discussed above in Section 3.2). In this preferred embodiment, if theMP selects non-default electrodes by touching “OTHER” 1218B on the MainDefibrillation Screen 1200, the central station monitors will displaythe pad setup screen which corresponds to the electrode pad system whichhas been attached to the victim. Three types of electrode pad systemsare discussed hereinbelow:

a) the five-electrode torso-shaped pad system (discussed in Section3.2);

b) the matrix pad system (discussed in Section 3.3); and,

c) the multiple single pad system (discussed in Section 3.4).

6.3.1.2.2.4.1 Five Electrode Pad Setup Screen

In a preferred embodiment of the invention, when a five electrode pad isattached to the victim, if the MP does not want to use the defaultselection of electrodes (pads α and δ) for defibrillation, he touches“OTHER” 1218B on the Main Defibrillation Screen 1200. The system willthen display screen 1290, the Five Electrode Pad Setup Screen, shown inFIG. 31. From this screen the MP can select any combination ofelectrodes for defibrillation energy application. (The screen can alsobe used to select the electrodes used for pacing energy application andfor ECG recording, when the five-electrode pad is in use and the defaultselections of pacing and/or ECG electrodes are not desired.)

For example, the MP might want to apply defibrillation energy betweenthe α and δ pads. (This example is also presented in Section 4.2 [SampleCardiac Arrest], Table 11, Time 2:31, and is discussed in Section4.3.1.1 [The MP Decision to Change the Defibrillation Vector for theSecond Shock].) To do so, working from Screen 1290, he touches:

1) “PAD α” 1292A; then,

2) “AND” 1294; then,

3) “PAD ε” 1292E; then,

4) “ACCEPT” 1296.

Touching “ACCEPT” 1296 returns the MP to the Main Defibrillation Screen1200.

Touching the “AND” button demarcates the completion of the cathodalelectrode selection and is followed by the start of the anodal selection(or vice versa). This approach allows the MP to use more than twoelectrodes and, in such a situation, to let the system know whichelectrodes are to be electrically common. For example, if the MP desiresto administer a shock in which the δ and ε electrodes are electricallycommon, and in which energy is applied between the a electrode and thecomposite δ/ε electrode, working from Screen 1290, he touches:

1) “PAD α” 1292A; then,

2) “AND” 1294; then,

3) “PAD δ” 1292D; then,

4) “PAD ε” 1292E; then,

5) “ACCEPT” 1296.

Because of the need to specify multiple pads while working from thisscreen, changing a selection by over-writing, as was the method for someother screens, would not result in clear specifications. Therefore, the“CANCEL” button 1298, allows the MP to delete the entire electrode entryand start all over. (In an alternative embodiment, only the lastelectrode choice would be deleted by touching “CANCEL”. Each successivetime it is touched would result in the deletion of the next priorelectrode choice.) If the MP changes his mind about non-defaultelectrodes, and decides to use the default electrode pair, he can simplytouch “DEFAULT” 1300, which selects the α and δ electrodes, and returnsthe MP to the Main Defibrillation Screen.

Screen 1290 illustrates a method of displaying prior shocks that differsfrom the “SHOW LAST” and “SHOW SAVED” buttons on the Main Defibrillationand on the Pulse Shape Screen. The “PRIOR ATTEMPTS” section of the FiveElectrode Pad Setup Screen 1290 lists, in tabular form, the sequence ofelectrode and energy specifications for each prior shock. In a preferredembodiment, it would also display the each pad selection as it ischosen; for example, if a fourth shock was being programmed, and the γand ε electrodes were being selected, then the fourth entry on thescreen would show:

a) “4) ______ VS ______ @______” prior to electrode selection;

b) “4) ______γ______ VS ______@______” after γ electrode selection; and

c) “4) ______γ______ VS ______ε______@______” after ε electrodeselection.

Alternate embodiments of the invention could use:

a) this format for other screens including screens 1200 and 1260;

b) the “SHOW LAST” and “SHOW SAVED” formats for screen 1290 (and for theother electrode pad setup screens discussed below—which are shown inFIGS. 30 and 32 with the “PRIOR ATTEMPTS” format of screen 1290);

c) hybrids of the “PRIOR ATTEMPTS” format and the “SHOW LAST”/“SHOWSAVED” format; and,

d) different formats which allow the MP to access information aboutprior attempts.

The electrodes on the five electrode pad, in addition to theirdefibrillating function, can also be used for ECG recording (see above)and for pacing the heart (see below). Screen 1290 can be use in any ofthese three situations, when the MP desires non-default electrodechoices. The choice of electrodes for one of these three functions (e.g.defibrillation) need not be the same as the choice for another (e.g.pacing).

In a preferred embodiment, the screen which the MP used to select screen1290 will determine which of the three functions (defibrillation, pacingor ECG recording) is specified by his electrode choices. For example, ifthe MP is working from the Main Defibrillation Screen 1200 and touches“OTHER” 1218B, the electrodes he then selects on screen 1290 will be thedefibrillation electrodes. If the MP arrived at Screen 1290 from theMain Defibrillation Screen, but then wished to select pacing electrodes,he would touch “PACE CONFIGURATION” 1304, and then enter his choice ofpacing electrodes in the same manner as was done for entering thedefibrillation electrodes. The “SHOCK CONFIGURATION” button 1302 letsthe MP select shock electrodes if he arrives at screen 1290 from eitherthe Initial ECG Screen (FIG. 29) or from the Main Pacing Screen (FIG.38). The “ECG CONFINGURATION” button 1306 lets the MP select ECGelectrodes if he arrived at screen 1290 from either the MainDefibrillation Screen or the Main Pacing Screen. In a preferredarrangement of this embodiment, there is an on-screen indication ofwhich of the three functions—defibrillation, pacing or ECG—is beingselected. For example, if the MP is selecting the shock electrodeconfiguration, the words “SHOCK CONFIGURATION” of button 1302 would beeither highlighted, backlit, blinking, etc.

The Five Electrode Pad Setup Screen 1290 is intended for use withelectrode pad 204A (FIG. 5A), in which each electrode may function as anECG electrode or an electrode for energy delivery. This pad does notcontain electrodes intended only for ECG recording. A setup screen whichwould accommodate electrode pads 204B and 207 (FIGS. 5B and 5C) withfive defibrillating electrodes and 7 additional ECG electrodes is notshown. Its appearance would be analogous to that of screen 1290, and theselection of non-default defibrillating electrodes would be identical tothe above description for the use of screen 1290.

6.3.1.2.2.4.2 Matrix Electrode Pad Setup Screen

In a preferred embodiment of the invention, when a matrix electrode padis attached to the victim, if the MP does not want to use the defaultselection of electrodes for defibrillation, he touches “OTHER” 1218B onthe Main Defibrillation Screen 1200. The system will then display screen1310, the Matrix Electrode Pad Setup Screen, shown in FIG. 30. A typicalarray of default matrix pad electrodes for the composite right-sidedelectrode would be a combination of nine electrodes: A1-A3, B1-B3 andC1-C3 rendered electrically common upon the appropriate command to theportable unit. A typical array of default matrix pad electrodes for thecomposite left-sided electrode would be a combination of nineelectrodes: G1-G3, H1-H3 and J1-J3 rendered electrically common upon theappropriate command to the portable unit. From screen 1310 the MP canselect any combination of matrix pad electrodes for defibrillationenergy application. He selects matrix pad electrodes by touching thebuttons 1312 that correspond to the matix pad electrodes that he wantsto include. (The screen can also be used to select the matrix padelectrodes used for pacing energy application and for ECG recording,when the matrix electrode pad is in use and the default selection is notdesired.)

For example, the MP might want to apply defibrillation energy betweentwo more widely separated groups of electrodes than those specified asthe default. To do so, working from screen 1310, he touches:

1) “A1”, then “A2”, then “A3”; then,

2) “B1”, then “B2”, then “B3”; then,

3) “C1”, then “C2”, then “C3”; then,

4) “AND” 1314; then,

5) “H1”, then “H2”, then “H3”; then;

6) “J1”, then “J2”, then “J3”; then,

7) “K1”, then “K2”, then “K3”; then,

8) “ACCEPT” 1316.

After each of the matrix electrode selection buttons is touched, thelabel within the button (i.e. “A1”, “A2”, “A3” etc.) is visuallyhighlighted, allowing the MP to easily keep track of his choices.

The buttons “AND” 1314, “ACCEPT” 1316, “CANCEL” 1318 and “DEFAULT” 1320function in the same manner as the corresponding buttons on theaforementioned Five Electrode Pad Setup Screen 1290.

In a preferred embodiment of the invention, there is a “PRIOR ATTEMPTS”area of screen 1310 which shows the matrix electrode combinations whichwere used in prior defibrillation attempts. As shown in FIG. 30, thosematrix electrodes selected to form composite electrodes at the time ofprior defibrillation attempts may be represented by filled in boxes (andthose matrix electrodes not used may be represented by non-filled inboxes), in a miniature version of the matrix electrode pad. In apreferred embodiment of the invention, touching within one of thebuttons 1322 which contain the miniature matrix pad representations,results in highlighting of all of those matrix electrode buttons 1312corresponding to the filled in 1322 selections. This enlargement step,reduces the chance of an error. If the MP then wishes to choose thedisplayed matrix electrode pattern for shock administration, he touches“ACCEPT” 1316.

The energy and other shock-related parameters associated with aparticular prior attempt, though not shown in FIG. 30, could be shown ifdesired.

Since the selection of matrix electrode combinations is potentially moretime consuming than the selection of electrodes on non-matrix pads, analternate embodiment would display, within screen 1310, a menu of othercommonly used matrix electrode combinations—even if they had not beenselected during the current victim's prior defibrillation attempts.These other commonly used combinations could be displayed instead of, orin addition to, prior attempts involving the current victim.

Other time saving approaches may include (but are not limited to):

a) the ability to select two adjacent matrix electrodes (e.g. A1 and B1)simultaneously by touching the corresponding buttons simultaneously.This could also be accomplished with four adjacent buttons (e.g. A1, A2,B1 and B2) simultaneously;

b) the ability to select a 3 by 3 array of matrix electrodes (e.g. A1,A2, A3, B1, B2, B3, C1, C2 and C3) by touching the center electrode (B2,in the example) twice. Alternatively, another button labeled “ACTIVATE 3BY 3 MATRIX” could be added to screen 1310, which would be touched afterB2 is touched, to activate the aforementioned nine electrodes.

c) the ability to select a 3 by 4 array of matrix electrodes (e.g. eachof the A, B, C and D matrix electrodes) by touching the two inner matrixelectrodes (B2 and C2) twice;

Alternatively, another button labeled “ACTIVATE 3 BY 4 MATRIX” could beadded to screen 1310, which would be touched after B2 and C2 aretouched, to activate the aforementioned twelve electrodes;

d) the ability to select a rectangular array of matrix electrodes bymovement of the computer mouse 314 (FIG. 3)—e.g. by clicking the mousebutton and holding it down starting at the upper left corner of therectangle, and dragging to the lower right corner and then releasing themouse button;

e) the ability to shift an already selected rectangular array ofelectrodes in the up, down, right or left directions, by using the fourcorresponding arrow keys on the keyboard.

In a preferred embodiment of the invention, various precautions aretaken to avoid the selection of matrix electrodes that may result in:

a) impossible matrix electrode combinations (e.g. where a particularmatrix element is listed as part of both the right-sided and the leftcomposite electrodes);

b) medically unreasonable electrode combinations (e.g. where both theright and the left composite electrodes are too close together [Aspecific example would be the selection of the nine matrix electrodes incolumns E, F and G for the right sided composite electrode and theselection of the nine electrodes in columns H, J and K for the leftsided composite electrode.]); or

c) situations that would cause a medically undesirable high currentdensity because of small composite electrode area (e.g. if only a singlematrix electrode (e.g. A1) was used as a composite electrode).

Methods for preventing or discouraging the use of potentially unwiseelectrode choices include:

a) locking out impossible and highly unreasonable choices, anddisplaying a message to the MP, explaining the reason for the lock-out,on the lower portion of the central station monitor 330. (See FIG. 3;The lower portion of 330 displays “MAJOR SYSTEM PROMPTS/MESSAGES TOMP”.)

b) for unconventional or possibly unwise choices, displaying a messageto the MP on the lower portion of the central station monitor 332. (SeeFIG. 3; The lower portion of 332 displays “MINOR SYSTEM PROMPTS/MESSAGESTO MP”.) The message could ask the MP to touch a “YES” button to confirmhis intention to go ahead with the selection;

c) for composite electrode choices which have already failed and areselected again, a minor system prompt on monitor 332 could be displayed.

The “SHOCK CONFIGURATION,” “PACE CONFIGURATION” and “ECG CONFIGURATION”buttons 1324, 1326 and 1328 are analogous in function to buttons 1302,1304 and 1306 on the Five Electrode Pad Setup Screen 1290, and on-screenindication of which of the three electrode functions is being selectedis provided.

6.3.1.2.2.4.3 Multiple Single Pad Setup Screen

FIG. 32 shows screen 1340, used by the MP when the portable unit is usedwith two or more pads which contain single defibrillating electrodes.Buttons 1342A-1342D, corresponding to each of four single electrodes,are analogous to buttons 1292A-1292E on the Five Electrode Pad SetupScreen 1290. This screen could be used with two, three or fourdefibrillating electrodes. A screen which accomodates more than fourelectrodes is possible.

During system operation, the MP would select one or more electrodes,then “AND” 1344, then another group of one or more electrodes, and then“ACCEPT” 1346. In a preferred embodiment of the invention, the MP wouldknow the anatomic location of the enabler's placement of each of pads#1, #2 . . . by having observed their placement.

The remainder of the Multiple Single Pad Electrode Screen 1340 and itsuse, is identical to the Five Electrode Pad Setup Screen, except for aslight difference in the spatial arrangement of the buttons.

6.3.1.3 Unconventional Defibrillation Methods

Although not incorporated into the above discussion of pulse shape andelectrode selection methodology, it would be possible to apply differentwaveforms between different electrode pairs. For example, “waveform A”could be applied between electrode pad #1 and electrode pad #2;“Waveform B” could be applied between electrode pad #3 and electrode pad#4 (or between electrode pads #2 and #3). Situations in which three ormore waveforms are applied to non-identical pairs of electrodes wouldalso be possible. Each waveform could carry a different energy. Thismulti-waveform approach would require the presence of a) additionalscreen selections to accommodate this variation, and b) additionaldefibrillator circuits within the PU. Such a situation is shownschematically in figure XX.

Situations in which combinations of electrode pads are used are alsopossible. For example, one of the five electrode pads or the matrixelectrode pad, could be used with one or more single electrodes placedon the victim's back, or elsewhere. Alternatively one of the fiveelectrode pads or a conventionally placed matrix electrode pad, could beused along with a matrix electrode pad placed on the victim's back. Thismulti-pad approach would require the presence of additional screenselections to accommodate this variation. As long as only one waveformis used no additional PU defibrillating circuits would be necessary.Additional defibrillator circuits within the PU would be required onlyif more than one waveform is used.

6.3.1.4 Paths From Main Defibrillation Screen

Besides paths to screens which allow for the specification ofnon-default defibrillation settings (FIGS. 30-32 and 34-36), three otherexit pathways are available:

a) “GO TO ANTI-TACHY PACING” 1220 is accessed to allow an MP to attemptto terminate certain tachycardias by the technique of overdrive pacing.These tachycardias may occur after a defibrillation attempt (See Section6.3.2, below).

b) “GO TO MAIN PACING SCREEN” 1222 is accessed to allow an MP to performbradycardia pacing. Bradycardia may occur after a successfuldefibrillation (See Section 6.3.3, below).

c) “GO TO MAIN MENU” 1224 allows the MP to then go to any other screen.

6.3.2 Anti-Tachycardia Pacing Screen 6.3.2.1 General Considerations

FIG. 37 shows the Anti-Tachycardia Pacing Parameters Screen 1350. In apreferred embodiment of the invention, the MP can use it to cause the PUto administer bursts of rapid ventricular pacing, in an attempt toterminate an episode of ventricular tachycardia.

In a preferred arrangement of this embodiment, the MP selects either the“ALL DEFAULT VALUES” button 1352, or selects up to five non-defaultvalues which specify the anti-tachycardia pacing parameters.

6.3.2.2 Default Values

Typical values of anti-tachycardia pacing default parameters wouldinclude:

a) a pacing cycle length which is 82% of the tachycardia RR interval;

b) 8 pacing impulses;

c) an inter-burst decrement (the amount of decrease in paced RR intervalbetween two successive burst pacing attempts) of 10 MSEC;

d) an intra-burst decrement (the amount of decrease in paced RR intervalbetween successive beats within a burst) of 0 MSEC; and,

e) a last R to S1 interval (the interval from the last tachycardiaR-wave to the first ATP stimulus) of 80%.

Among the aforementioned five parameters, the factors which most clearlyincrease the aggressiveness of anti-tachycardia pacing are:

a) a smaller % RR;

b) a larger inter-burst decrement; and,

c) a larger intra-burst decrement.

To deliver the pacing stimulation to the victim specified by the defaultparameters, the MP would touch “ALL DEFAULT VALUES” 1352 followed by“DELIVER” 1354.

6.3.2.3 Non-Default Values

If the MP wished to select a non-default value of ATP rate, he wouldtouch one of the nine buttons labelled “72”, “74”, “76”, “78”, “80”,“84”, “86”, “88” or “90”. If he wished to select a value which did notcorrespond to the labels on the aforementioned buttons, he could either:

a) select “OTHER” 1358, and then use the keyboard to enter the desiredvalue; or,

b) select “90” and then touch the “+2” button 1360A once if he wished toselect a value of 92%, twice if he wished to deliver a value of 94%,etc.; or,

c) select “72” and then touch the “−2” button 1360B once if he wished toselect a value of 70%, twice if he wished to deliver a value of 68% etc.

If the MP wished to specify the default value for ATP pacing rate (butwished to specify non-default values for one or more of the other ATPparameters), he would touch either “82” (if this value had been set asthe default value) or “DEFAULT” 1356A.

If the MP wished to select a particular pacing rate (the increment abovethe tachycardia rate being a measure of aggressiveness), rather thanusing the aforementioned approach based on the RR interval of thetachycardia, he could:

a) select “OTHER” 1358; then,

b) use the keyboard to enter “RATE”; then,

c) use the keyboard to enter the numeric value of the pacing rate.

In an alternate embodiment of the invention, the MP could select thepacing rate by formatting the ATP Parameters Screen so that:

a) a sub-menu of pacing rates is displayed instead of the sub-menu of %RR shown in FIG. 37; or,

b) both pacing rate and % RR sub-menus are displayed; or,

c) either a sub-menu of pacing rates or a sub-menu of % RR is displayedat any one time; and a button is present which lets the MP select one ofthese two sub-menus.

For each of the four remaining ATP parameters, the MP would then go onto either: a) select a default value using one or more of “DEFAULT”buttons 1356B-1356E; or b) select a particular non-default value. Onceeach of the five ATP parameters had been selected, the MP would touch“DELIVER” 1354, to cause the PU to stimulate the victim with thespecified ATP. If at any point before the delivery of the ATP, the MPwished to change his choice for one or more of the already selected ATPparameters, he could do so by over-writing the already-selected choice.

The ability to display the parameters of prior pacing attempts, or todisplay a “library” of selectable ATP parameter “packages”, though notshown in FIG. 37, is an optional feature.

6.3.2.4 Paths from Anti-Tachycardia Pacing Screen

An unsuccessful anti-tachycardia pacing attempt may result inacceleration of ventricular tachycardia to a faster (and hence, lesswell tolerated) rate, or conversion of ventricular tachycardia toventricular fibrillation. In either of these two cases, prompt deliveryof a shock is desirable. By touching “GO TO MAIN DEFIB SCREEN” 1362, theMain Defibrillation Screen 1200 is accessed.

Occasionally, following the successful pace termination of VT, a slowheart rate occurs. By touching “GO TO MAIN PACING SCREEN” 1364, the MainPacing Screen (see below) is accessed, allowing the prompt delivery ofpacing at an appropriate rate (typically 50 to 100 beats per minute).The MP may also need to access the Main Pacing Screen if he wishes tochange any of the parameters of the anti-tachycardia pacing pulse(amplitude, contour, electrodes) from the default values (see below).

6.3.3 Bradycardia Management Screens

Bradycardia or slow heart rate may be observed a) following the MPtermination of any tachycardia or fibrillation (as was the case duringthe sample cardiac arrest described in Section 4.2, Table 11,Time=2:43), b) as the victim's initial heart rhythm. External electricalstimulation of the heart, external pacing, as is known in the art, canresult in an acceleration of the heart rate to the rate of the externalstimulation. In a preferred embodiment of the invention, the portableunit is capable of performing such pacing, under the direction of theMP.

The Main Pacing Screen 1370 (FIG. 38) is the MP's primary access to thecontrol of bradycardia pacing. The screen layout is similar to that ofthe Main Defibrillation Screen 1200, and most of the control buttonshave analogous functions on each of these two screens. The selection ofbradycardia pacing parameters will consist of either using defaultvalues (which requires only the Main Pacing Screen) or will require theaccessing of one or more other screens for the selection of:

a) non-default values of pacing pulse amplitude (FIG. 39); and/or,

b) non-default values of bradycardia pacing rate (FIG. 40); and/or,

c) non-default values of pacing pulse shape (FIG. 36); and/or,

d) non-default values of pacing electrode configuration (FIGS. 30-32);and/or

e) non-default values of “sensing”, that is, the use of ECG informationshowing spontaneous activity of the heart, to reset the timing of pacingimpulses.

6.3.3.1 Paths to Main Pacing Screen

The routes by which the MP arrives at the Main Pacing Screen 1370 are:

a) from the Main Defibrillation Screen (FIG. 33), if bradycardia isobserved after the administration of a shock;

b) from the Anti-Tachycardia Pacing Parameters Screen (FIG. 37), ifbradycardia is observed after tachycardia termination by ATP;

c) from the Initial ECG Screen (FIG. 29), following the recognition ofbradycardia as the initial victim rhythm;

d) from any of the screens that may be used to select non-default valuesof pacing parameters (FIGS. 30-32, 36, 39 and 40); and,

e) from the Screen Menu (FIG. 43).

6.3.3.2 Method of Operation: Bradycardia Pacing Screens 6.3.3.2.1Default Values

If the MP decides to pace using default values, he selects “ALL DEFAULTVALUES” 1372, followed by “DELIVER” 1374 (as was the case for theinitial pacing during the sample cardiac arrest described in Table 11,Time: 2:46). Touching “DELIVER” results in the transmission of a commandfrom the central station to the portable unit to deliver pacing with theprogrammed parameters, via the appropriate electrodes. Touching “STOPPACING” 1375 results in the transmission of a command from the CS to PUto terminate pacing.

A possible set of default values is:

a) Amplitude=maximum

b) Rate=60 beats per minute (“BPM”);

c) Waveform=monophasic;

d) Pacing electrodes=α and δ (when using the five electrode pad); and,

e) Sensing=off.

The actual default values may be set in a number of ways which werediscussed above (see Section 6.3.1.2.1).6.3.3.2.1.1 Common versus Different Parameters for Bradycardia Pacingand for Anti-Tachycardia Pacing

In the default mode of operation for screen 1370, the selected pacingand sensing parameters (except, of course, for rate) are applied forboth bradycardia pacing and for anti-tachycardia pacing. The MP may,however, wish to use different parameters for these two types of pacing.If so, he can set them separately by touching “BRADY ONLY” 1386A or “ATPONLY” 1386C prior to entering choices intended for only that one type ofpacing. If he is entering ATP values, he a) does not enter a value forrate on screen 1370, and b) does touch “GO TO ANTI-TACHY PACING” 1388after having entered the non-rate parameters.

If the MP, at any time after touching either “BRADY ONLY” 1386A or “ATP”ONLY 1386C wishes to return to the default mode of simultaneouslysetting both bradycardia and ATP pacing parameters (other than rate),the MP touches “BRADY AND ATP” 1386B and then enters the commonparameters.

In a preferred embodiment of the invention, the default setting for theaforementioned common pacing parameters (viz. “BRADY AND ATP”) isindependent of the default setting for the other pacing parameters (e.g.amplitude, waveform, etc.) For example, if “BRADY ONLY” 1386A had beenselected, followed by “ALL DEFAULT VALUES” 1372, the result would bethat all bradycardia pacing values would be set to default values (butthat ATP pacing parameters, if already set with one or more non-defaultvalues, would be unchanged). Also, if the system is operating in theBRADY AND ATP mode, then the selection of a non-default value ofamplitude, for example, does not require the MP to touch “BRADY AND ATP”1386B to reaffirm this.

6.3.3.2.2 Non-Default Values

Instead of selecting “ALL DEFAULT VALUES” 1372 for the pacingparameters, the MP may select one or more non-default values. Anon-default value is selected by touching 1376B (non-default amplitude);1378B (non-default rate); 1380B (non-default waveform); 1382B(non-default pacing electrode configuration); or 1384B, 1384C or 1384D(the three non-default sensing buttons). Each of these non-defaultbuttons (except for the non-default sensing buttons, which are discussedbelow) leads to a different pacing detail screen (1260, 1290, 1310,1340, 1400 [Pacing Amplitude Screen] and 1420 [Bradycardia Pacing RateScreen]) which contains a menu which lists possible non-defaultsettings. The approaches to displaying these pacing detail screens arethe same as for displaying the defibrillation detail screens (seeSection 6.3.1.2.2).

Once the MP has selected a non-default value and has then returned tothe Main Pacing Screen, he may either a) select default values for theother pacing parameters, or b) select other non-default values for oneor more of the remaining parameters.

To select a default value for one of the pacing parameters, the MPtouches the appropriate one of buttons 1376A (default amplitude), 1378A(default rate), 1380A (default waveform), 1382A (default pacingelectrode pattern) or 1384A (default sensing). An example of thisapproach is presented in Section 4.2 which describes an hypotheticalcardiac arrest (see Table 11, Time 2:57-2:59: After selecting anon-default value for the pacing rate, the MP selects default values foreach of the other four parameters.)

As was the case with the defibrillation screens, the selection of thedefault value of a pacing parameter preferably results in visualemphasis or highlighting of the word “DEFAULT” within the button (1376A,1378A, 1380A, 1382A or 1384A) that corresponds to the default selection.

Non-default values are also preferably displayed on the Main PacingScreen (FIG. 38) in an approach analogous to the defibrillation display:

a) A non-default value of pacing amplitude, if selected, would bedisplayed as a number within button 1376B, replacing the word “OTHER”.

b) A non-default value of pacing rate, if selected, would be displayedas a number within button 1378B, replacing the word “OTHER”.

c) A non-default pulse contour, if selected, would be displayed, alongwith the numerical parameters which specify it, in the Pulse ContourMiniscreen 1380C. This screen-within-screen would be analogous to itscounterpart element 1216C on the Main Defibrillation Screen.

d) A non-default pacing electrode pattern, if selected, would bedisplayed in Miniscreen 1382C. The content of this Miniscreen would showthe pattern of electrodes selected for pacing energy delivery, presentedin a manner similar or analogous to the display in element 1322 (FIG.30). With electrode pads other than the matrix electrode pad, thoseelectrodes selected for pacing energy delivery could be either (i)displayed in Miniscreen 1382C, or (ii) listed within button 1382B,replacing the word “OTHER”.

e) There are three non-default sensing choices. The amplitude of thelargest R-wave (if one is present) and the lead from which it isrecorded would be displayed in button 1384B. The amplitude of the R-wavecorresponding to the lead selected for pacing would be displayed inbutton 1384C. The R-wave amplitude corresponding to a manually selectedchoice of sensing lead other than the aforementioned would be displayedin button 1384D.

When all of the pacing parameters have been selected, the MP touches“DELIVER” 1374, to deliver pacing via the electrode configuration, andwith the parameters that have been selected. This format differsslightly from that of defibrillation, in that the step of touching an“ACCEPT” button (element 1206, FIG. 33), though required fordefibrillation, is not required for pacing. Two reasons for requiringthis step only during defibrillation are: a) Since capacitor chargingwithin the PU takes a number of seconds, the requirement for touching asecond button after charging is complete allows the MP to abort a shockif VT or VF terminates during charging; and b) The additional stepserves a fail-safe function, making accidental or inappropriatedefibrillation less likely.

As was the case when all of the pacing parameters are the default ones,when the MP touches the “STOP PACING” button 1375, the CS transmits acommand to the PU for pacing cessation.

As was this case with the review of previous defibrillation efforts, theMP may want to review previous pacing efforts. The method for suchreview is analogous to that discussed in Sections 6.3.1.2.2 and6.3.1.2.2.3 above: “SHOW PREVIOUS” 1394A, “SHOW NEXT” 1394B, “SAVESAVED” 1396A and “SAVE” 1396B on the Main Pacing Screen all functionidentically to their counterparts on the Main Defibrillation Screen.

6.3.3.2.2.1 Pacing Amplitude Screen

FIG. 39 shows one possible example of a screen which would allow themedical professional to control the energy of the PU pacing pulse. Thescreen is arrived at by touching “OTHER” 1376B on the Main PacingScreen, or from the Screen Menu (FIG. 43). The default value ofamplitude is the maximum pacing amplitude of the PU, selected bytouching the “MAX” 1402 button. Buttons 1404 (“⅕ MAX”), 1406 (“⅖ MAX”),1408 (“⅗ MAX”) and 1410 (“⅘ MAX”) allow for the selection of lesservalues of amplitude; These choices might be considerations in asemi-conscious or conscious victim. Another method of specifying theamplitude would be for the MP to touch the button labeled “OTHER”, 1412,and then enter the desired value of amplitude via keyboard; The keyboardentry would then replace the word “OTHER” on the screen. The keyboardentry could be: a) a fraction other than the choices in buttons 1404,1406, 1408 and 1410; or b) a numeric value, followed by the desiredunits (e.g. “V” for volts or “A” for milliamps). After entering a valuefor the amplitude, touching “ACCEPT” 1414 returns the MP to the MainPacing Screen 1370, where the selected value of pacing amplitude appearswithin button 1376B.

If the MP decides to change his choice before touching “ACCEPT”, he mayover-write the choice. If he changes his choice after touching “ACCEPT”,he would touch “OTHER” 1376B on the Main Pacing Screen, which wouldreturn him to the Pacing Amplitude Screen 1400.

Embodiments of the invention are possible in which:

a) there are a greater or a lesser number of buttons which select pacingamplitude, and in which the values that they specify are fractions otherthan fifths (e.g. ⅓ and ⅔);

b) the buttons which specify the amplitude specify actual output values(i.e. numbers of volts or milliamps), rather than fractions of themaximum output;

c) both the pacing amplitude and pulse width are selected on the samescreen;

d) the amplitude is fixed;

e) the amplitude and pulse width may be varied, but not independently;i.e. in which the MP chooses from a menu of pre-specified pairs ofvalues for pacing amplitude and pulse width; and/or,

f) the amplitude is not fixed, but is determined by the system in whichan “auto-capture” feature determines if “capture” (i.e. cardiacdepolarization) has occurred, and utilizes an algorithm to optimizepacing amplitude and/or pacing pulse width.

6.3.3.2.2.2 Bradycardia Pacing Rate Screen

FIG. 40 shows one possible example of a screen which would allow themedical professional to control the rate of PU pacing. The screen isarrived at by touching “OTHER” 1378 b on the Main Pacing Screen, or fromthe Screen Menu. The buttons labelled “30” through “125” (indicating therate in beats per minute [BPM]) allow the MP to select a rate in thisrange. If after reaching the Bradycardia Pacing Rate Screen, the MPchanges his mind and decides to utilize the default value of 60 BPM, hecan select it by touching either a) button 1422 labeled “DEFAULT=60”, orb) the button labeled “60”. Another method of specifying the rate wouldbe for the MP to touch the button labeled “OTHER” 1424 and then enterthe rate via the keyboard. The keyboard entry would then replace theword “OTHER” in button 1424. After entering a value for the rate, the MPtouches “ACCEPT” 1426 which returns him to the Main Pacing Screen 1370,where the selected value of pacing rate appears within button 1378B. TheMP can change his choice of pacing rate using a method analogous to thatdescribed for changing pacing amplitude in the previous section.

Embodiments of the invention are possible in which:

a) the rate is specified only by keyboard;

b) the rate is specified only by buttons with pre-selected values, as inFIG. 40;

c) the buttons display values of rate other than those in FIG. 40;and/or,

d) the rate is not programmable.

6.3.3.2.2.3 Pulse Shape Screen/Pacing

In a preferred embodiment of the invention the MP may control the widthor shape of the pacing pulse by touching button 1380B on the Main PacingScreen. This takes him to Pulse Shape Screen 1260. In a preferredarrangement of this embodiment, the words “PACING PULSE” inside ofbutton 1286 would then either blink or be otherwise visually emphasized,making it clear that the screen selections apply to the pacing pulsewidth and shape, not the defibrillator pulse width and shape.

The default value of pacing waveform is monophasic. The MP specifies oneor more parameters using Pulse Shape Screen 1260, in a manner analogousto that described for the defibrillation pulse (see Section6.3.1.2.2.3). He then touches “ACCEPT” 1270 to return to the Main PacingScreen, where the pulse width is then indicated in button 1380B, and thepulse contour and any other pulse descriptors selected are shown inPulse Contour Miniscreen 1380C.

Embodiments of the invention are possible in which:

a) the pulse shape screen for pacing is not identical to the pulse shapescreen for defibrillation;

b) the MP cannot control any parameter of pulse contour except the pulsewidth;

c) the MP cannot control any parameter of pulse contour, including thewidth;

d) the MP controls of pulse shape and/or width are keyboard based;and/or,

e) the MP control of pulse width is via a single screen form which bothpacing amplitude and pulse width are controlled.

6.3.3.2.2.4 Pacing Electrodes

If the MP wishes to select a non-default value of pacing electrodeconfiguration, he can do so by touching button 1382B on the Main PacingScreen. This takes him to the appropriate one of the three Electrode PadSetup Screens shown in FIGS. 30-32. On arrival at the setup screen, the“PACE CONFIGURATION” button blinks or is visually highlighted,indicating that the screen is being used to set this function. The MPthen makes his electrode choice in a manner analogous to the process forthe selection of defibrillation electrodes (described in 6.3.1.2.2.4).He then touches “ACCEPT” to return to the Main Pacing Screen. Theselected configuration is indicated within Miniscreen 1382C, and, whenfeasible (as discussed above), within button 1382B.

6.3.3.2.2.5 Pacemaker Sensing

In a preferred embodiment of the invention, pacing by the PU isasynchronous in the default mode, i.e. the PU pacemaker output is notinfluenced by a voltage applied to any of the electrode pads. Thealternative to asynchronous pacing, the so-called “demand mode,” allowsthe PU-based pacemaker to sense the victim's own cardiac activity, andto reset its pacemaker timing cycle upon sensing such activity, in amanner which is well known in the art.

The value of the asynchronous mode of operation is that it avoids thepotential problem of inappropriate inhibition of pacemaker output bynon-cardiac signals-signals which may be generated by movement of eitherthe victim or the cable which connects the PU with the victim. The valueof the demand mode is that it prevents “competitive pacing”: thegeneration of unwanted pacing stimuli which may cause a deterioration inthe victim's cardiac status.

If the MP desires to pace in the demand mode, he has three options,which are discussed hereinbelow.

6.3.3.2.2.5.1 Sensing from the Electrode Arrangement with the LargestR-Wave

The first demand mode option is for the MP to touch button 1384B on theMain Pacing Screen, which causes the system to select the electrode pairwhose R-wave has the largest amplitude, for sensing. This pair may ormay not be the same as the electrode pair used for pacing. Each memberof the pair may be a single electrode, or a composite of multipleelectrodes rendered electrically common.

6.3.3.2.2.5.2 Sensing from the Electrode Arrangement used for Pacing

The second sensing option, accessed by touching button 1384C, is to usethe pacing electrodes for sensing. With both the first and the secondoption, the MP is aided, in a preferred arrangement by the display ofthe numeric value of the R-wave amplitude within boxes 1384B and 1384C.

6.3.3.2.2.5.3 Sensing from an Electrode Arrangement Selected by the MP

The third demand pacing approach involves having the MP examine the ECGwaveform on a number of ECG lead arrangements, and then select hischoice for sensing from among the examined arrangements. In thisembodiment of the invention, when the MP touches “OTHER” 1384D, theInitial ECG Screen 1180 (FIG. 29) is displayed. The R-wave amplitude foreach of the ECG recordings is advantageously displayed within thebuttons 1182 to the left of each tracing. If the MP does not see an ECGlead that he wishes to use among those displayed on the Initial ECGScreen, he then touches “AUTO LEAD SEARCH” 1186 which results in thesubstitution of the three ECG leads with the largest R-waves for thosedisplayed on the lower ECG rows of the Initial ECG Screen. Touching“AUTO LEAD SEARCH” on that screen (FIG. 29) a second time causes thedisplay of the three electrode arrangements with the next largestR-waves. This process of ECG review may be repeated until either a) theMP identifies a desirable ECG sensing arrangement, or b) the MP decidesto pursue one of the aforementioned other sensing formats. If at anytime the MP wishes to go back to a previously shown group of three ECGtracings, he touches “PREVIOUS LEAD GROUP” 1187.

If the MP identifies a possibly desirable ECG sensing electrodearrangement, he selects it by touching the button 1182 to the left ofthe desirable ECG tracing. Each of the two electrodes or the componentsof each of the two electrode groups that make up the sensing electrodearrangement are optionally displayed in Miniscreen 1184, using a formatsimilar to element 1322 of FIG. 30. Various optional on-screen displayformats may tell the MP whether sensing of the selected ECG format wouldbe effective including: a) the overlay of a pair of horizontal linesparallel to the baseline of the selected tracing, which demarcate thesensing threshold; and b) the superimposition of a dot above each sensedevent. If the MP desires to increase or decrease the sensitivity hecould use either: a) the arrow up and arrow down key to the right of thetracing, or b) the keyboard arrow keys. If the MP wishes to change theselected lead to another, he does so by touching a different one of the1182 buttons, which over-writes his previous selection. After completingthe selection process (whether successful or not) the MP touches button1190 “MAIN PACING SCREEN” which returns him to screen 1370. The systemwill utilize the electrode arrangement corresponding to the last buttonselection among elements 1182 for sensing purposes. If no electrodearrangement was selected, it will prompt the MP (either by highlightingeach of buttons 1384A, 1384B and 1384C) or with a text message shown onthe Major System Prompts Monitor 330 (FIG. 3). If the MP does not wishto use the electrode arrangement corresponding to the last selection onscreen 1180, he selects one of the other sensing options on the MainPacing Screen 1370.

When the five electrode pads with separate ECG electrodes 204B and 207(FIGS. 5B and 5C) are utilized, an alternate approach to sensingelectrode selection is possible. It entails displaying a screenanalogous to screen 1290 (the Five Electrode Pad Setup Screen) butcontaining in addition, touch sensitive buttons which allow theselection of ECG electrodes. The MP then selects sensing electrodes bytouching the corresponding buttons on the screen, as an alternateapproach to selecting an ECG lead (for sensing) from screen 1180.

There are a very large number of other possible methods of selectingsensing electrodes. Variations in the sensing electrode selection methodinvolve both algorithmic features (i.e. the sequence of buttonselections) and display features (the screen formats, keyboard formatsand hybrid formats).

A beneficial result of providing all of these options and tools for theMP, is that the MP can make use of this flexibility in exercising hisbest judgment while resuscitating the victim.

6.3.3.2.3 Termination of Pacing

Termination of pacing was discussed above in Sections 6.3.3.2.1 and6.3.3.2.2. If the MP terminates pacing and later wishes to resume it,touching “DELIVER” 1374 on the Main Pacing Screen will result in theresumption of pacing with the all of the same parameters as were ineffect at the moment of pacing cessation.

6.3.3.3 Paths from Main Pacing Screen

Besides paths to screens which allow for the specification ofnon-default pacing settings (FIGS. 30-32, 39 and 40), three other exitpathways are available:

a) “GO TO ANTI-TACHY PACING” 1388 takes the MP to the Anti-TachycardiaPacing Parameters Screen 1350 (FIG. 37).

b) “GO TO MAIN DEFIB SCREEN” 1390 takes the MP to the MainDefibrillation Screen 1200 (FIG. 33). Should VT or VF occur duringpacing or pacing setup, this allows the MP to have rapid access todefibrillation.

c) “GO TO MAIN MENU” 1392 takes the MP to the Screen Menu (FIG. 43),which allows the MP to then go to any other screen.

6.4 MP-Directed PU Diagnostic Check and Maintenance Screen

FIG. 41 shows the screen 1490 used by the MP or a technical/maintenanceperson for checking PU and SU function (see Section 8.1 and FIGS. 55Aand 55B).

The MP can obtain a list of problem PUs by touching 1491, and viewingthe list in screen-in-screen 1500. In a preferred embodiment of theinvention, these units would have detected a fault during their dailyself check and called it in to the CS (see Section 8.1). He can viewpreviously downloaded data about a selected unit by touching 1492.

The MP contacts the PU by touching 1493 to select the transmission mode(e.g. either through the SU, or directly; either wireless or wire), andthen touching 1494. This results in a handshaking routine shown in FIGS.12D, 12E, 12F, 13B and 140, leading to the setting of the master controlunit 130 to state 4.

The MP then touches 1495 to download and display the results of dailyPU-SU checks, and then clears this memory, if he chooses to, by touching1496.

Besides the PU and SU communication equipment daily evaluation dataavailable from the download, the MP can further assess this by issuingthe central station beacon, touching 1506, to test the PU and SUreceivers. He can evaluate audio input and output at the PU by touching1504, which allows him to either issue an audio tone or voice promptoriginating at the PU. If necessary he can then adjust audiocharacteristics of the PU with options 3B (see above and Table 20) and6A. He selects from among these choices by touching 1505B or 1505Crespectively, each of which leads to a menu of options displayed onscreen 1500. The MP can also cause the production of one or more tonesor a voice originating at the CS, have it transmitted and enunciatedthrough the PU speaker, and listen to it through the PU microphone. Thismay lead to other adjustments involving options 3 or options 6.Alternatively, if at that point the MP wishes to make othercommunication enhancement adjustments involving the CS, he can selectfrom the option 1 menu by touching 1505A, or option 8 menu by touching1505D.

The MP can assess the high voltage circuitry by touching 1508, followedby 1510, and, if he chooses, 1509. He can display the current videoimage by touching 1511. If he chooses, he can deploy the video boom bytouching 1512 and working from the video control screen. In a preferredembodiment of the invention, he can extend the boom sufficiently toallow the flexible portion of it to bend a full 180 degrees, allowinghim to visually inspect the PU. Alternatively, he could observe the PUwithout such bending if a there was a properly oriented mirror on thewall opposite the PU, i.e. by looking at the PU in the mirror.

If the MP detects a problem that requires remedy, he has the followingoptions:

a) If the problem is remediable by a software manipulation, he can loadadditional software by first touching 1513 to enable this function;

b) If the PU requires replacement, he can show the nearest PU (either inservice currently, or not yet in service) by touching 1514;

c) He can send a text message which will appear on one of the PU screens156;

d) He can contact the CS administrator by touching 1516, or himselfdispatch a maintenance person to the faulty PU; and/or

e) He can activate the PU alarm by touching 1517.

6.5 Master Triage Screen

In the event of an overflow in emergency call volume, the MP or acentral station administrator or “CSA” can redistribute emergency eventsto other central stations or to MPs who may be working with a computeroutside of a central station. As shown in FIG. 42, the CSA works fromscreen 1550 to do this.

Unassigned cases appear at the top of the screen in boxes 1552A (whichshows an emergency waiting to be handled by an MP) and 1552B (whichshows a PU which has called in because of an abnormality picked upduring its daily diagnostic check). Additional such cases would appearin box 1552C and in the boxes to its right. These boxes may showidentifying information and a few word statement of the problem and itsurgency, as assessed by a call screener.

In the lower portion of the screen the status of each working MP isaccessed, one per broken line box. Thus MP #1 in CS #1 is controlled inthe upper left box with buttons 1559A-C. The CSA can see that the MP isworking on a victim by box 1559A. If the CSA wishes to speak to the MPhe touches 1559B. If he wishes to view the case, he touches SHOW CASE1554, followed by 1559A. This results in the display of the victim ECGof this case in screen 1557 and the event log in 1558. The CSA can usethese to assess whether this MP could handle a second simultaneous case.If the CSA wishes to assign a second case to the MP, the CSA touches thefollowing sequence of three touch sensitive buttons:

a) the button corresponding to the case to be assigned (whether as yetunassigned, or currently assigned to another MP); then

b) the MOVE CASE button 1556; and then

c) the button corresponding to an unassigned spot.

For example, if none of the three MPs in CS #1 was available to handlethe unassigned case indicated by box 1552A, the CSA could assign it toMP #2 in CS #2 by touching 1552A, then 1556, and then 1560.Alternatively, the MP could assign the case to MP #3 in CS #1 bytouching 1552A, then 1556 and then 1561.

6.6 Main Screen Menu

FIG. 43 shows a touch sensitive screen 1600 which allows the MP to gofrom it to any other screen. The upper portion of this screen1602A-1602H shows the contents of each of the active CS screens. Thelower portion shows a list of all of the touch sensitive and non-touchsensitive screens.

The MP selects a screen for display by touching the box with itsdescription and then touching the destination screen from among1602A-1602H. Split screen display would be accomplished by touchingsequentially touching one screen title box, then touching a second one,and then touching the destination screen from among 1602.

If the MP wishes to select the Main Screen Menu when it is notdisplayed, he can touch “CONTROL M” on the keyboard or some otherdesignated “hot-key.” If he wishes to clear a choice he can touch“CONTROL C” or a different hot key.

In addition to the screens already discussed the MP can view:

a) medical information from databases maintained at the CS, at anotherCS or elsewhere;

b) medical information about the victim if it is available either from adoctor's office, a hospital record, a pharmacy or another database. Suchviewing would involve transmission of medical information in compliancewith local and federal statutes, as would all transmissions ofinformation during and after the MP encounter with the victim. Inaddition, if the victim or a person with the victim has a magneticallyor optically readable card which carries his vital medical information,it can be scanned by inserting into 185 (FIG. 8), and displayed on theCS console;

c) legal information relating to the termination of therapy, whether itbe federal, state or local statute, and legal information about thedocumented wishes of the victim, if any, and if such documentation isavailable, whether it be a “living will” or other advanced health caredirective;

d) information about choices that he has made which the system claims tobe medically unreasonable (e.g. the selection of defibrillationelectrodes which are too close together). The MP is informed by promptsof the CS screens, and can get further information including the reasonwhy the choice is felt to be unwise and alternate recommendations bytouching the appropriate boxes on the Main Screen Menu; and

e) information about AED performance (by touching “AED STATUS”) in theevent of a communication interruption requiring a change in mastercontrol from state 1 (MP guided therapy) to state 2 (AED guidedtherapy). Another time that the MP might choose “AED STATUS” is if he isunsure about whether a rhythm is VF or asystole and thinks that signaldegradation during communications is hindering his analysis. In such acircumstance he could find out the AED assessment of the rhythm, sincesuch assessment is based on data which may not be distorted; and

f) the Event Log.

6.7 Command Confirmation and Event Log

FIG. 44 shows a screen which documents all MP actions and all telemetryrelating to PU events.

In the case of MP commands, the presence of each of four confirmationsignals (or the absence of one or more) is indicated in the fourindicator boxes 1704. These boxes could turn green when as eachconfirmation signal is received, and red if one is not (as per the flowdiagram in FIG. 24), or could give a numeric value, if appropriate. Forexample, the right-most box after “CHARGE PU CAPACITORS” could indicateeither the charge time, the voltage prior to discharge, or both.

In the case of MP telemetry, each event is documented by a singleindicator box 1702. This could also be a binary indicator, or could givea numeric value. For example, in the case of the “ECG SIGNALS,” ameasure of the amplitude could be displayed.

The information in this log becomes part of the victim's permanentmedical record. It is preserved and handled using the security measuresthat are professionally and legally appropriate.

7. Block Diagrams: Units and Major Components of the System 7.1 ThePortable Unit

FIG. 45 shows an embodiment of the portable unit 104. The victim 102 isattached to it via electrode pads 210 which can record his ECG, andadminister electric current to perform cardiac pacing or defibrillation.Switching circuits 133 are used to switch the pads between ECG recordingon the one hand, and pacing or defibrillation on the other. In oneembodiment of the invention, the PU interfaces with an electrode pad204B (FIG. 5B) in which some electrodes may be used only for ECGrecording.

ECG signals are amplified and digitized by analog to digital converterand amplifier 118. The three outputs of 118 are to:

a) the PU memory 123, from which they may be retrieved at a later timeduring the event for use by the MP, or after the event, by appropriatelyauthorized and identified medical personnel;

b) to encoder 120, at which the signals are processed for transmissionvia transmitter 122, to antenna 162, from whence they are transmitted tothe central station either directly, or via a stationary unit or otherrepeater unit (see FIG. 59); and

c) microprocessor 129.

Commands from the medical professional are received by receiver 126 viaantenna 162, and then are decoded by decoder 127. The decoder hasmultiple outputs (see FIG. 51A, 51B and discussion below) including:

a) the MP's voice signals which are processed by audio circuits 134A andheard by the enabler through speaker 146;

b) commands sent by the MP to circuits 131 which control the output ofthe pacemaker and defibrillator 132;

c) the PU memory, where each command is securely maintained, timestamped by digital clock 125, as part of the victim's medical record;

d) commands from the MP to microprocessor 129 which determine the stateof the master control unit, which determines the overall control of thePU; and

e) commands sent by the MP to switching circuits 133 which controlelectrode pad selection for defibrillation, pacing and ECG recording.

In the event of communication failure which prevents either initial orongoing communication between the PU and the central station, the backupAED function allows the unit to function at a basic level. Themicroprocessor in this situation processes and analyzes ECG signals and,based on such analysis and on prior programming provides outputs to thecircuits 131 which control the pacemaker and defibrillator 132. A recordof these outputs is also stored in memory 123. Redundancy in thetransmitter and the receiver makes a communication failure less likelyto occur. In the figure, three channels are shown for each of thetransmitter and receiver. The ability of the MP or the system to haveaccess to multiple channels and multiple communication modalities makesthe communications system robust.

The transmitter and receiver, both shown attached to antenna 162 neednot necessarily share the same antenna.

In a preferred embodiment of the invention, each command issued by theMP results in the issuance of multiple confirmation signals, which letthe MP know that the command has been properly processed and executed.In FIG. 45, an output of the pacemaker and defibrillator unit 132 whichcarries such confirmation signals goes to encoder 120 from whence theyare transmitted to the MP.

Other information transmitted to the MP includes:

a) the enabler's voice, via microphone 148 (FIG. 6A);

b) blood pressure data from cuff 172; and

c) oxygen saturation data from transducer;

each of which goes to analog to digital converter and amplifier 124Afrom whence it goes to the encoder and then the transmitter.

All data transmissions containing victim information are transmitted inan appropriately encrypted and secure format. If the MP wishes todownload events from memory, he may send the appropriate command and doso. He may also upload new information to memory concerning PU functionand maintenance.

FIG. 46 shows another embodiment of the portable unit which illustratesadditional features of its operation.

Elements along the boundary of the unit correspond to their placement asshown in FIGS. 6A and 8. The front of the unit (i.e. the side that facesan enabler as he approaches the unit) includes video screens 156, videocamera 154, speaker 146, microphone 148 and activation button 106. Atelephone handset 150 is shown in the front in this figure; it islocated on the side in FIGS. 6A and 6B.

The rear of the unit, i.e. the side which faces away from the enablerinitially includes touchdown and removal sensor 178 and theelectromagnetic lock and lock sensor 182, both of which supplyinformation to microprocessor 129. The microprocessor also providescontrol signals for the electromagnetic lock. Connectors 188 and 186convey information and power between the PU and the stationary unit.

A telephone jack 153 and antenna are shown on the sides of the PU.

The PU contains rechargeable batteries 1804 which are charged from thestationary unit via 186. Power is distributed, circle B1, to each energyrequiring component.

The output of video camera 154 is amplified by video amplifier 124B;microphone outputs are amplified by 124A. In a preferred embodiment ofthe invention the outputs of each, along with ECG signals and signalsfrom digital clock 125, memory 123 and microprocessor 129, afterencoding, are subject to data compression at block 1800. Outgoing datais then routed at block 1802 to any of:

a) the telephone system via data connection 188 to the SU;

b) the telephone system via transmitter 122;

c) the telephone system via jack 153;

d) the internet or a non-public data sharing network via either 188, 122or 153; or

e) the central station or a repeater unit (see FIGS. 58 and 59) viaradio frequency or microwave transmission.

The management of data routing may be performed by the MP or byequipment in the central station via signals sent to 1802 via the PUreceiver 126; or b) by microprocessor 129.

Incoming data is decompressed at by 1800. Decoded information, inaddition to the functions discussed above, is also used to control thevideo boom 112 (FIG. 6B) and camera via amplifier 134B.

During the handshaking process, there may be need to adjust thecharacteristics of the PU transmitter and receiver, the PU audiocircuits, other PU input and output circuits, data routing and themodem. The source of such adjusting signals may be from either end, i.e.the MP/central station or the PU microprocessor.

During the communications handshake, PU transmitter and modemadjustments may occur, and are among the operations referred to as“options 6B” (see FIG. 14 and table 20). PU receiver and modemadjustments may occur, and are among the operations referred to as“options 3A”. Adjustments in the routing of data from the PU, referredto as “options 7” may occur as well. These adjustments may be initiatedby the PU microprocessor which, in FIG. 46, is shown to control theseunits. They may also be initiated from the central station end, byeither the MP or equipment within the CS; Such control is indicated asoutput from the decoder 127 to the transmitter/receiver 122, 126 and todata routing and modem 1802.

The characteristics of audio circuits 124A which amplify and process theenabler's voice are controlled by signals transmitted from the centralstation or by the PU microprocessor. These characteristics (as well asthe characteristics of non-audio inputs) may be adjusted by commandsfrom the CS during the data-commands handshake or the audio handshake;Such adjustments have been referred to as “options 6A” (see FIG. 14 andtable 20). Circuits 134A which amplify and process the MP's voice (aswell as those which control non-audio outputs) may also be adjustedduring the aforementioned two handshakes; Such adjustments have beenreferred to as “options 3B.”

The PU interfaces with the victim via circuits 131, 132 and 133(discussed above) which connect to the electrode pads. In FIG. 46, theconnection to an electrode pad with five defibrillating and sevensensing electrodes, one of many possibilities, is shown schematically.Ribbon cables 222 and 224 (see FIG. 7B) connect to universal connectors220 which link the electrode pads to the PU so that they arereplaceable.

All appropriate victim-related, command related, PU telemetry, audio andvideo information is stored in memory via circle ME.

7.2 The Stationary Unit

The SU 108 has three main functions.

a) It serves as a relay unit, communicating with both the PU and thecentral station, thereby extending the range and flexibility ofcommunications.

b) It is the source of power for the PU rechargeable batteries.

c) It locks the PU to a wall or other stationary object, preventingtheft or inappropriate use.

Logic and control circuits 144B supply information 1918 to switches 144Cand 144D. While the PU is attached to the SU, Switch 144D is directlyconnected to the PU input and output data streams via connectors 190 (onthe SU side) and 188 (PU side). As shown in the figure, depending on theposition of the switch, it can connect the data stream to either ahard-wired interface with the public telephone system 1814 or to a longrange transmitter 138 and receiver 140 which may access the cellulartelephone system, or communicate via antenna 164 over radio frequency ormicrowave channels which are not part of the telephone system. Althoughthe switches depicted have two positions, they could allow the selectionfrom among more than two choices, including broadband options.

Switch 144C controls the input and output to the PU short rangetransmitter 142 and receiver. Once the PU is detached from the SU, thehard-wired data connection via connectors 190 and 188 is no longerfunctional. As of the time of PU-SU separation, the PU would thereforebe likely to communicate with the central station either:

a) directly, through its own transmitter and receiver, as depicted inFIG. 45; or

b) indirectly, in which case the PU transmitter and receiver may be incommunication with the SU short range transmitter and receiver. Theseshort range units are linked to the long range transmitter and receivervia switch 144C; or

c) indirectly, with the short range transmitter 142 and receiver linked,via switch 144C and telephone interface 1814 to the telephone system.

The information which determines the position of switches 144C and 144Dcomes from decoder 144A which obtains signals from each of:

a) receiver 140, via block 1818B and block LR 1818A;

b) telephone interface 1814; and

c) receiver 136, via block 1816B and block SR 1816A;

d) the portable unit, via block 1820B and block X 1820A.

The MP or equipment within the central station would control routing viaa) or b) above, while the PU would control it via c) or d) above.

Power supply 1810, supplied with line current via line cord and plug196, supplies both the SU rechargeable batteries 1812 and the PUbatteries via connectors 192 (SU) and 186 (PU).

Locking projection 194 projects into the PU allowing the two to belocked together, when the PU is not in use.

7.3 The Master Control Unit

The master control unit 130 determines the source of control for themost important functions of the PU, as outlined in Table 1 and describedin Section 1.3.1.2. The crux of its function is the setting of whocontrols pacing and defibrillation.

Control signals for the master control unit come from the MP in thecentral station, to the PU and are decoded by the PU decoder (FIG. 51Aand 51B). FIG. 48 shows the five possible control signals from thedecoder outputs:

a) SET MC=0, block MC0 1939A;

b) SET MC=1, block MC1 19341A;

c) SET MC=2, block MC2 1943A;

d) SET MC=3, block MC3 1945A; and

e) SET MC=4, block MC4 1947A.

Setting MC=0 results, block 1832, in the powering down of powerconsuming functions such as video and transmitter circuits.

Setting MC=1, done by the MP after a successful handshaking process withthe PU and enabler results in:

a) allowing the MP to control all of the major functions of the PU,block 1830;

b) enabling release of the PU-SU lock, block 1834;

c) enabling defibrillator control circuits that allow charging 131B,discharge 131A and pacing 131C; and

d) block 1840, powering up the video screens.

Setting MC=2 differs from the MC=1 setting in that control of pacing anddefibrillation are by the on-board AED/P when MC=2. This is the defaultsetting once the PU has been activated by a button press. A signal fromthe central station, sent after the communications and data-commandshandshakes have been properly executed, is required to set MC=1.

Setting MC=3 enables control of the PU by the EMT. Block 1838. Sincethey would use the device in the same way that a medical professionaldoes, pacing and defibrillation are enabled when MC=3.

Setting MC=4 is the prelude to the PU diagnostic check, block 1842. Thesignal for this may come form the central station in which case it movesfrom the PU decoder via block 1947B (FIG. 51A) to block MC4 1947A, tothe master control unit 130, to block 1842, to block 1844B, to block CK1844A starting the PU checking routine. The starting signal may alsocome from a clock 2100 within the PU (see FIG. 55A) via block 1947C toblock MC4 1947A. MC=4 does not enable defibrillator discharge, a safetyfeature, though it does enable high voltage charging, so that theintegrity of the high voltage circuits may be evaluated. MC=4 also doesnot enable PU-SU lock release.

7.4 The Central Station

FIG. 49 shows a block diagram of the central station. Information aboutan incoming emergency call may arrive via either the telephone system1880 or by radio receiver 346. Routing circuits and modem 1850 allow forthe handling of multiple simultaneous calls (see FIG. 42). After datadecompression 1852, the CS decoder 348 decodes incoming signals andsends them to:

a) memory 1858,

b) microprocessor 1854;

c) audio amplifier and processing unit 352A, from whence they go tospeaker 320; and

d) video amplifier and processing unit 352B, from whence they go toscreen 308, showing a video of the victim.

Incoming ECG, blood pressure and oxygen saturation data is sent from thedecoder to the microprocessor where it is properly formatted anddisplayed on screens 302, 304 and 306 (see FIG. 3). Commandconfirmations are displayed as part of the event log on screen 338(FIGS. 3 and 44) and signal quality on screen 336 (FIGS. 3 and 25).Other displays include a reproduction of the displays on the PU screens156, displayed in the CS on screens 322 and 324 (FIGS. 3 and 28), andthe real time (from clock 1856) and the elapsed time, displayed onscreens 340 and 342.

During the communications handshake, CS transmitter and modemadjustments may occur, and are among the operations referred to as“options 1B” (see FIG. 14 and table 20). CS receiver and additionalmodem adjustments may occur, and are among the operations referred to as“options 8A”. Adjustments in the routing of data from the CS, referredto as “options 2” may occur as well. These adjustments may be initiatedby the CS microprocessor which, in FIG. 49, is shown to control theseunits. Microprocessor output MS 1855 leads to the transmitter via block1869, transmitted data routing and modem via block 1865, the receivervia block 1873 and received data routing and modem via block 1852.

The characteristics of audio circuits 360A which amplify and process theMP's voice, as well as the characteristics of non-audio inputs, may beadjusted during the data-commands handshake or the audio handshake. Suchadjustments have been referred to as “options 1A”. Circuits 352A whichamplify and process the enabler's voice and circuits which controlnon-audio outputs may also be adjusted during the aforementioned twohandshakes. Such adjustments have been referred to as “options 8B.” TheCS microprocessor is shown to control these units. Microprocessor outputMS 1855 leads to audio amplifier circuits 360A and via blocks 1855 to1867 to amplifier circuits 352A. The microprocessor also monitors signalquality at audio amplifier 360A, at audio amplifier 352A (block 1853D toblock MT 1853A), at main receiver 346 (block 1853B to block MT 1853A)and at transmitter 358 (block 1853D to block MT 1853A).

The MP inputs commands to the microprocessor via any of keyboard 312,mouse 314, joystick 310 (for adjusting PU video boom 112) or any oftouch or light sensitive screens 328, 330, 332 and 334. In a preferredembodiment of the invention, screens 330 and 332 display major and minorsystem prompts and messages to the MP (shown in FIG. 3). These includeinformation about any command which is either incompatible with thesystem or which may be recognized by the system as potentially unwise,messages which indicate failure to receive a confirmation signal, andmessages indicating the detection of a potential or actual faults in asystem component.

The commands output the microprocessor and proceed to encoder 356, todata compression 1862, and to transmitted data routing and modem 1864.After this they go either to transmitter 358, with transmitted signalsemanating from antenna 1868, or to telephone lines 1880. All encodedsignals are time stamped by clock 1856 and stored in memory 1858. Thetransmitter also intermittently sends out a “central station beacon”signal which is used during the periodic diagnostic checking of the PUand the SU.

Other MP inputs include microphone 316 and video input 362. The latterincludes signals from the video camera showing the MP as well asinstructional material which the MP may wish to display for the enabler.These inputs are amplified by audio and video amplifiers 360A and 360B,and sent to the encoder from which they follow the same output route asMP commands.

Confirmation signals, discussed above, allow the MP to observe theprocess of command execution, and to assess a fault in this process.Confirmation signal #1 which confirms proper inputting of a commandentails routing of a signal from encoder 356 via block 1853F, via blockMT 1853A to microprocessor 1854 with display on screen 338.

A second confirmation signal is generated when the command is furtheralong in its transmission. If it is sent by wireless means, it reentersthe system via confirmation receiver 1872, passing through confirmationrouting 1874, to confirmation decompression 1876 and then toconfirmation decoder 1878. This decoder sends signals to the CSmicroprocessor 1854 and to the CS memory 1858 (via block 1860B to blockMR 1860A). (The other output of decoder 1878 also leads to the CSmicroprocessor, via the sequence of block 2028B, block CR 2028A (FIG.54), to block 1854C—the microprocessor portion which results in theformatting and display on CS screen 338).

The third and fourth confirmation signals arrive via main decoder 348and are discussed below.

A database and data storage system 344 may contain one or more of

a) information about the resuscitation system;

b) a medical database which may contain information about generalmedical issues or about the victim's medical data;

c) a legal database which may contain information about local andfederal laws concerning the termination of resuscitation efforts andwhich may contain specific information about the legal documentation ofthe wishes of a particular victim regarding resuscitation efforts;

d) information about the location, technical characteristics and repairhistory for each of the portable and stationary units with which the CSmay interact; and

e) information about the availability emergency facilities and personnelin the vicinity of any particular PU.

The system is powered by uninterruptible power supply 1866 which willpreferentially include many layers of backup. The MP will have access tostandard communication modalities including telephone 318.

7.5 The Stationary Unit Decoder

In order for the SU to perform its functions it requires access tosignals from the central station and from the PU. The decoding androuting of these signals is shown in FIG. 50.

The SU decoder 144A receives:

a) signals from the CS via the SU long range receiver 140;

b) signals from the CS (and possibly the portable unit) via phone andland line signals 1900;

c) hard-wired PU signals 1902 via the connectors 188 and 190; and

d) PU signals from the SU short range receiver 136.

One SU decoder output 1918B controls signal routing within the SU(discussed above in section 6.2). The output is applied to switches 144Cand 144D (FIG. 47).

Four of the SU decoder output control features of the SU transmittersand receivers:

a) Output 1904B controls the SU long range transmitter 138;

b) Output 1906B controls the SU long range receiver 140;

c) Output 1908B controls the SU short range transmitter 142;

d) Output 1910B controls the SU short range receiver 136.

These components may need to adjusted during any of the handshakingroutines.

The SU participates in certain aspects of the diagnostic checkingroutine (see FIGS. 55A and 55B) and this accounts for the remainingthree SU decoder outputs shown in the figure:

a) During the checking routine, the CS beacon signal must be properlyreceived by the SU long range receiver. Receipt of this signal 1912leads to block 1920B, to block SC1 1920A (FIG. 55B) where it becomes oneof the items in a diagnostic check which shows proper SU functioning.

b) During this diagnostic check, this aforementioned or another CSbeacon signal must be properly received by the SU short range receiver.Receipt of this signal 1914 leads to block 1922B, to block SC2 1922A(FIG. 55B) where it becomes another items which shows proper SUfunctioning.

c) Also during the diagnostic check, the PU short range transmittersends a test signal to the SU short range receiver. The decoded signal1916 leads to block 1924B, to block SC3 1924A where it registers properfunctioning of the involved components.

7.6. The Portable Unit Decoder

FIGS. 51A and 51B show the PU Decoder. It decodes and routes signalscoming in to the PU including those which set the master control unit,those which control the defibrillation, pacing and ECG circuits, thosewhich control the PU communications between the PU and the CS.

Signals enter the decoder 127 from the receiver 126. The decoder outputincludes:

a) PU receiver control signals 1938B which control receiver gain atvarious points, channel selection, signal conditioning and otherreceiver parameters;

b) PU transmitter control signals 1960B which control transmitter power,channel, modulation, signal conditioning and other parameters;

c) five signals, 1937B, 1940B, 1942B, 1944B and 1946B which set themaster control unit to each of states 0, 1, 2, 3 and 4 respectively.They are sent to the master control unit via blocks 1939B, 1941B, 1943B,1945B and 1947B respectively;

d) defibrillator control signals 1930B which control each parameter ofdefibrillation including pulse amplitude, pulse shape, synchronization,the onset of charging and delivery of the shock. These control signalsgo to defibrillator control circuits 131A, and then to defibrillatorcircuits 132A whose output pulse is applied to the electrode pads 200selected by the switching circuits of pad selection network 133A.Decoder signals 1932B control the electrode pad choices of network 133A;

e) pacing control signals 1934B which control each parameter of pacingincluding pulse amplitude, pulse shape, pacing rate, starting andstopping of pacing, sensing parameters (if any) during pacing andanti-tachycardia pacing features, if this modality is used. Thesecontrol signals go to pacing control circuits 131B, and then to pacingcircuits 132B whose output pulses are applied to the electrode pads 200selected by the switching circuits of pad selection network 133A. Thepacing electrodes may or may be the same as the defibrillationelectrodes;

f) control signals 1948B which determine the spatial positioning andorientation of the PU video boom 112;

g) control signals 1950B which control the PU video camera 154;

h) signals 1952B which contain the content for PU screens 156 and whichdetermine viewing parameters such as brightness and contrast;

i) signals 1954B which control the audio amplifier 124A for the enablervoice via microphone 148 (options 6A during the handshaking process);

j) signals 1956B which determine enabler listening parameters such asloudness and filtering (options 3B during the handshaking process); andother signals which carry the MP voice which are applied to the PU audioamplifier 134A and speakers 136;

k) signals 1958B which contain the alphanumeric coding of the PU voiceprompts (when used) which are stored in a read only section of the PUmemory 123;

l) signals 1962B which cause the data on the current medical event,stored in PU memory 123 (including victim physiologic information,telemetry and voice information, block 1964 and all decoder outputrecords, block 1966) to be read and transmitted to the CS;

m) handshake signals 1968B which are sent to the microprocessor andresponded to according to the previously described routine;

n) control signals 1970B for release of the PU-SU lock (FIG. 16B);

o) control signals 1972B for ECG recording which determine whichelectrode pads are recorded from, block 1973B to block EF 1973A to block133B, the ECG pad selection network; and which set ECG gain andfiltering parameters, block 1971B to block EA 1971A to block 118 ECGamplifier and signal conditioning circuits;

p) control signals 1974B for the blood pressure and pulse oximetrycircuits 1978; and

q) control signals 1976B which control the inflation of the PU bloodpressure device 172.

Confirmation signal #3 originates when a command arrives at the PUdecoder. For defibrillation and pacing, these signals go from blocks1936B and 1936E, respectively to block CS 1936A of the PU encoder (FIG.52) where they are processed and transmitted to the CS and displayed.These signals indicate that a command has properly traversed the CSprocessing unit, CS communications output, the CS to PU communicationslink, PU communications input, PU communications output, the PU to CSlink, CS communications input and CS processing output. All othercommands which originate in the CS will be associated with a similarconfirmation signal (not shown in FIGS. 51A and 51B).

Confirmation signal #4 indicates actual execution of the command. Suchfourth confirmation signals for defibrillation and pacing go from blocks1936C and 1936D respectively, via block 1936A to the PU encoder.

7.7 The Portable Unit Encoder

In order for the MP to make decisions about the management of a cardiacarrest of other urgent situation, he must be provided with victimphysiologic data. Such data, along with PU telemetry and communicationsinformation is encoded by the PU encoder 120, compressed at block 1800,appropriately routed at block 1802 and transmitted to the centralstation via direct wire, cable, or wireless route.

Signals which are encoded include:

a) signals 2000A from the ECG pads;

b) enabler audio signals 2001A;

c) the PU touchdown signal 2002A;

d) the SU-PU separation signal 2004A

e) SU-PU lock release telemetry data 2006A;

f) handshake signals 1968C;

g) the initial “button press” signal 2008A;

h) PU diagnostic checking data 2010A (see FIG. 55A and 55B);

i) PU global positioning signals 2012A (useful for tracking a unit whichis lost or stolen, or one which during operation has been movedsubstantially from the corresponding SU location);

j) data 2014A from the PU memory concerning the event in progress (maybe utilized if communication between PU and CS was interrupted and laterrestored);

k) victim video signals 2016A;

l) defibrillation pad identifier signals 2018A (indicating removal ofthe ECG pad cover during application to the victim);

m) defibrillation pad impedance data 2020A, indicating the adequacy ofcontact between the pad and the victim;

n) pulse oximetry data 1979A;

o) blood pressure data 1980A;

p) confirmation signals 1935A and 1937A (see section 7.6);

q) AED telemetry information 2022A (that may be sent during a partialcommunication failure, in which PU to CS communication is intact, but CSto PU communication is not); and

r) portable unit touch sensitive screen responses (see FIG. 15).

7.8 The Central Station Decoder

FIG. 53 shows the central station decoder and routing of signals whichemanate from it. Since it decodes signals which have been sent from theportable unit, its outputs generally have corresponding inputs to the PUencoder, shown in FIG. 52. Accordingly, such pairs of elements have beenassigned identical numbers, with the source element having an “A” suffixand the received element having a “B” suffix.

Signals reach the central station decoder 348 from the CS main receiverand modem after routing and decompression, elements 346, 1850 and 1852(FIG. 49).

Signals which are decoded include:

a) ECG signals 2000B. After signal processing and conditioning bymicroprocessor sub-unit 1854G, they are displayed on ECG screen 302;

b) enabler audio signals 2001B;. After audio signal processing asdescribed previously they result in the output of 320;

c) telemetry signals indicating PU events including the PU touchdownsignal 2002B, the SU-PU separation signal 2004B, the SU-PU lock releasetelemetry data 2006B and handshake signals 1968D. These signals go tomicroprocessor sub-unit 1854D for processing and formatting of telemetrysignals displayed on PU screen 338;

d) signals sent to the microprocessor sub-unit 1854A which are used forlogic functions including handshaking signals 1968D, the initial “buttonpress” signal 2008B, PU diagnostic checking data 2010B and PU globalpositioning signals 2012B;

e) data 2014B from the PU memory concerning the event in progress. Thisdata is sent to the CS memory 1858 which also stores all CS decoder andselected microprocessor outputs;

f) victim video signals 2016B. These are processed by 352B and displayedon screen 308;

g) defibrillation pad identifier signals 2018B and defibrillation padimpedance data 2020B which are processed and formatted by microprocessorsub-unit 1854F and displayed on screens 302;

h) pulse oximetry data 1979B and blood pressure data 1980B which areprocessed and formatted by microprocessor sub-unit 1854E and displayedon screens 306 and 304 respectively;

i) four confirmation signals for pacing, defibrillation and othercommands-confirmation signals #1 (coming from central station encoder[FIG. 54] via block CQ 2026A), confirmation signals #2 (coming fromcentral station confirmation receiver decoder 1878 via block CR 2026A)and confirmation signals #3 and #4, 1935B and 1937B—all of which areprocessed and formatted by microprocessor sub-unit 1854C and displayedon screen 338;

j) AED telemetry information 2022B and portable unit touch sensitivescreen responses 2024B, which along with other information to bedisplayed related to microprocessor logic functions, are processed andformatted by 1854B and displayed on CS screens 322, 324, 336, 340 and342.

7.9 The Central Station Encoder

FIG. 54 shows the central station encoder 356 and associated signals andcircuits.

MP commands, entered by CS inputting devices such as the touch sensitivescreens 328, 330, 332 and 334, the keyboard 312 and the mouse 314, areregistered by microprocessor 1854. All of these commands except thosedestined for the CS transmitter and data routing circuits are sent tothe CS encoder. These commands include:

a) defibrillation and pacing command signals 1930A and 1934A;

b) SU communication control signals including signals 1906A and 1910Afor the SU receivers, signals 1904A and 1908A for the SU transmittersand signal 1918A for SU data routing;

c) PU communication control signals including signal 1938A for the PUreceiver (options 3A), signal 1956A (options 3B) for MP and voice promptvoice processing at the PU, signal 1954A (options 6A) for enabler voiceprocessing at the PU, signal 1960A for the PU transmitter (options 6B)and signal 2038A for PU data routing (options 7);

d) master control unit state setting commands 1937A, 1940A, 1942A, 1944Aand 1946A which command the PU master control unit 130 to enter states 0through 4 respectively;

e) video control signals 1948A, 1950A and 1952A;

f) control signals for voice prompts 1958A;

g) control signals 1962A to allow the MP access to the PU event memory;

h) control signals 1932A for selecting the defibrillator and pacing padelectrode constituents;

i) handshake signals 1968A;

j) control signals for PU-SU lock release 1970A; and

k) control signals for victim physiologic data including signals 1972Ato select ECG pads and recording parameters, signals 1974A for bloodpressure and oxygen saturation data and signals 1976A for blood pressurecuff inflation and deflation.

Microphone 316 and video input 362, leading to audio and videoamplifiers 360A and 360B respectively, input the encoder with signals tobe sent to the PU.

The microprocessor outputs which do not go to the encoder are thosewhich control the CS transmitter (options 1B) and CS data routing(options 2). Transmitter control is via block 2040B to block TM 2042A;transmitter data routing is via block 2042B to block TDR 2042A.

Encoder output follows the sequence shown in FIG. 49 with datacompression 1862, routing 1864 and transmitter 358.

The encoder produces confirmation signals #1 for pacing 2034A,defibrillation 2036A and other functions 2032A. These confirm properentry of the command and proceed via block 2026C to signal processingand display.

8. Miscellaneous 8.1 Diagnostic Check

FIGS. 55A and 55B show a flow diagram for a diagnostic check of thePU-SU combination. The check may be initiated, block 2100, by either theclock within the PU (e.g. on a daily basis), or by the central station,block 2102. In the latter case, a signal is sent which initiates thehandshaking routine shown in FIGS. 12D, 12E, 12F, 13B and 140.

As each item is checked, the result of the check is classified assatisfactory or unsatisfactory. For example, if the PU battery check2104 shows satisfactory battery voltage and minimal deviation from theprevious day's value, then block 2106 leads to block 2110B, to block a2110A, resulting, block 2148, in the storage of the information in PUmemory. The CS will, in a preferred embodiment of the invention, performa periodic (e.g. monthly) check, during which the aforementionedinformation is downloaded. If, however, the results of the battery checkwere unsatisfactory, block 2106 leads to block 2108B, to block ν 2108A.This results in:

a) storage of the information in PU memory;

b) immediate notification of the CS; and

c) optional sounding of a PU alarm or indicator. Each of the 21remaining diagnostic evaluations follows a similar format. Normal testresults leads to blocks 2110C through 2110Y, then block σ 2110A, andinformation storage. Abnormal test results leads to blocks 2108C through2108Y, then block ν 2108A, and contacting the CS. The tests include:

a) blocks 2112 and 2114, checking for SU-PU electrical continuity overassigned pins in data connectors 188 and 190;

b) block 2116, checking the SU battery;

c) block 2118, checking all clocks;

d) block 2120, checking the global positioning system within the PU. If,block 2122, the PU position is substantially the same as the previousday, the result is considered normal;

e) block 2124, checking the PU touchdown sensor. If, block 2126, it isin the intermediate position, the result is considered normal;

f) block 2128, checking the SU-PU lock. If, block 2130, it is locked,the result is considered normal;

g) block 2132, checking the PU activation button. If, block 2134, it isin the open position, the result is considered normal;

h) block 2136, checking the master control unit state. If, block 2138,the value is 4 (i.e. appropriate for a diagnostic check), the result isnormal;

i) block 2140, charging the high voltage capacitors. If, block 2142, thevoltage, charge time, and decay time are all normal, the result isnormal;

j) block 2150, the PU issues an audio tone or voice prompt.

It simultaneously records and analyzes the sound, block 2152. If, block2154, loudness and sound quality are adequate, the result is considerednormal. This test allows for the evaluation of both audio input andoutput at the PU;

k) block 2156, the PU transmits a test signal to the SU short rangereceiver. The receiver passes the signal through the SU decoder (FIG.50) whose output leads to block SC3 1924A via the hard-wire data linkbetween the PU and the SU, and evaluation of the returned signal. Asatisfactory quality signal, block 2160, indicates adequate functioningof the PU short range transmitter and the SU short range receiver;

l) block 2162, the SU short range transmitter, transmits a test signalto the PU receiver and the PU, block 2164 assesses the quality of thereceived signal. If signal quality is adequate, the result is normal;

m) in blocks 2168 and 2170, the SU hard-wire telephone hookup isconfirmed;

n) in blocks 2172, 2174, 2176, 2178, 2180 and 2182, each of thereceivers in the PU and SU is checked for its ability to detect the CSbeacon signal. Information from the SU decoder, via block SC1 1920A andblock SC2 1922A is used for the assessment of the two SU receivers;

o) in blocks 2184, 2186, 2196 and 2198, the oxygen saturation and bloodpressure systems are evaluated; and

p) in blocks 2188, 2190, 2192 and 2194, the defibrillator pads arechecked to make sure that their connection to the PU is secure, thattheir backing is intact and that the resistance between adjacentelectrodes is in the expected range.

8.2 Universal Connectors

FIGS. 56A-56F show a series of universal connectors for attaching eachtype of electrode pad to the PU. There is a single male connector 220,FIG. 56A, which is situated at the PU end of each connection. Its thirtyfour pins 2300 are sufficient in number to accommodate the matrixelectrode pad and two identifier pins (see below). It has twonon-conducting locator pins 2302 to facilitate connection of twoconnectors.

FIG. 56B shows the female universal connector 218C which would attachthe matrix electrode pad (FIG. 5F) to the PU. In the figure, receptacles2304, which accommodate the pins of the male pad, are labeled to showtheir correspondence to the matrix electrode pad elements. Pins 1-4 and2-4, are rendered electrically common by a short length of conductingwire 2306 within the connector. Each type of electrode pad has a uniqueassignment for its two common pins. This allows the PU to determinewhich type of pad is attached to any of its male connectors (see FIG.7B).

Thus, if at any time either an enabler, an EMT or a maintenance personattaches the wrong pad to a particular PU connector, the system and theMP will be able to detect this action. In a preferred embodiment of theinvention, the MP can also know when the backing of a pad as beenremoved (see FIG. 5E).

FIG. 56C shows the female universal connector 218A for the fiveelectrode pad without separate ECG electrodes, 204A. Conductive element2308 will cause the pins which plug into locations 3-3 and 3-6 to beelectrically common, the signature for this type of pad. Pins 1-1, 1-2,1-3 and 2-1 are electrically common with the α electrode 230 of the pad(see FIG. 5A). The assignment of four pins provides a lower resistanceconductor for the defibrillating current. (The outline around each groupof four pins in the figure is for illustrative purposes and has nofunctional value.) Elements 2306B show the four conductive receptacleswhich are electrically common with the pad's β electrode. The pad'sremaining three pad electrodes have pin assignments which are indicatedby 2306C, 2306D, and 2306E. The pin assignments are selected so that thepins with the greatest electrical potential difference during a shockare as far apart as is practical on the connector.

FIG. 56D shows the female universal connector 218B for use withelectrode pad 204B, having five large defibrillating electrodes andseven small ECG electrodes. The defibrillating electrode pin assignmentsare the same as those in FIG. 56C. There are seven additional pins 2310,2312, 2314, 2316, 2318, 2320 and 2322, which are assigned, one to eachof the small ECG electrodes. The seven letters shown in the figurecorrespond to the identical letters which label the small electrodes inFIG. 5B, and are for illustrative purposes. Conductive element 2324renders pins 3-4 and 3-5 electrically common, and is the identifier forthis type of electrode pad.

FIG. 56E shows a female universal connector 218D for use with multiplesingle electrode pads 210. Such an approach is illustrated in FIG. 5G.The pin assignments are the same as those for four of the five electrodepads in FIGS. 56C and 56D. For this pad, the conductive element 2326lies between locations 3-1 and 3-2.

FIG. 56F shows a universal connector 218E intended to be used withmini-pads 211. Since the mini-pads are ECG pads and do not carry largeamounts of current, single pin receptacle assignments 2330A-2330D areacceptable. Conductive strip 2328 identifies this type of universalconnector.

8.3 Network of Central Stations

FIG. 57 shows a network of central stations. The network serves twopurposes. First, in the event of a major malfunction in the centralstation, whether it be equipment related, due to a fire ormeteorological event, backup central station functioning would beprovided. Second, in the event of an overflow situation—i.e. too manycalls for the number of MPs staffing a particular centralstation—additional MPs from a less busy CS could help to distribute theload.

The figure shows a master central station and router 2350 whichcommunicates with a series of portable units 2358A, 2358B, 2358C . . .through either:

a) wireless links via antenna 2351 and PU antennae 2359A, 2359B, 2359C .. . ;

b) the SUs 2356A, 2356B, 2356C, associated with each of the PUs, whichlink to the CS via either the telephone lines 2354 or SU antennae 2357A,2357B, 2357C . . . .

The broken lines extending from each PU indicate that the PU isoperating primarily by wireless connection, either to the SU or to thetelephone system or other public or private communication network.

Additional central stations 2352A, 2352B . . . are linked to the masterCS by either their antennae 2353A, 2353B . . . or by telephone lines2354

During operation, the MP in the master CS, working from screen 1550(FIG. 42) can transfer one or more cases to MPs in any of the other CSs(see above). He can transfer unassigned cases, or cases that are inprogress. The transfer can be over telephone lines 2354 or by wirelessmeans.

In an alternative embodiment, every central station in the network wouldbe capable of being the master central station. In yet another variant,any or all of central stations 2352A, 2352B . . . could be replaced by asolo MP operating on a personal computer, which is part of a wirelessnetwork. The solo MP could work on a regular shift, or could be“activated” only when high volume conditions necessitate hisparticipation.

8.4 Multiple Communication Modalities and Routes

FIG. 58 depicts the various routes and means by which the PU, the SU andthe CS can communicate. Each pair can communicate:

a) using the public or a private telephone system, over land lines, LL;

b) using the public or a private cellular telephone system, depicted bybroken lines, CP;

c) by line-of-sight radio frequency communication, RF-LOS;

d) by non-line-of-sight radio frequency communication, RF: non-LOS;

e) using satellite links 2360 and 2362.

The figure shows each of these modalities in place between the membersof the PU-SU pair and of the SU-CS pair, but each modality may alsoapply to the PU-CS pair.

Mixed modalities are possible a) when communication is via the SU and b)within any link. For example, the link from PU to SU may be over thecellular telephone network, while the SU-CS link may be by satellite. Inanother example, the link between any pair from among the PU, SU and CSmay in part be cellular and in part over land lines.

Private broadband cable systems may be used for any of theseconnections. The internet, accessed via the public telephone system orby cable access, may serve for any of these links.

8.5 Multiple Possible Routes and Relays Between PU and CS

The PU 104 may communicate directly with the CS 300, or one or moreintervening relay units may link the PU with the CS. Already discussedare the situations in which a) the intermediate relay is the SU alone,or b) the SU and another PU (see Table 13 above). It would also bepossible to link the PU 104 with the CS via

a) multiple other SUs (e.g. 108A and 108B);

b) repeater units 2370, deployed in strategic locations where the localcommunication system may not be as robust as desirable;

c) combinations of SUs (e.g. 108A and 108B) and repeater units 2370, asshown in FIG. 59.

The intention of the multiplicity of segments in the PU-CS link would beto produce a more robust communications link than would have been thecase if a smaller number of units performed the linkage.

When more than one stationary unit is used to link the PU and the CS,such that one or more “idle” SUs, i.e. SUs not currently carrying victiminformation from its associated PU, is used:

a) means would be provided for allowing the PU associated with an idleSU to very rapidly come on-line, if an emergency arose in its vicinity.Such a situation would require rapid redirection of the PU-CS link whichwas using the idle SU;

b) means would be provided for selecting the constituents of amulti-element link between the PU and the CS. Such means could liewithin the CS, within each SU or both within the CS and the individualSUs.

8.6 Control of an Implantable Cardioverter-Defibrillator by the MP

Implantable cardioverter-defibrillators, “ICDs,” as are known in theart, make their own assessment of a patient's rhythm and treat withpreprogrammed parameters. In certain circumstances, the expertise of theMP may allow for better choices of therapy than the choices made by theICD. Such circumstances include:

a) the situation in which the patient may be getting one or more shocksfor a rhythm such as sinus tachycardia, atrial fibrillation or atrialflutter, which the ICD failed to distinguish from ventriculartachycardia or ventricular fibrillation;

b) the situation in which the patient should have gotten a shock but didnot, e.g. because VT occurred at a rate which was less than theprogrammed rate detection rate of the ICD, or because so-calleddetection enhancements, as are known in the art (e.g. sudden onset),were programmed in such a way that the ICD could not make a proper VTdiagnosis; and

c) the situation in which a patient will receive or has been receivingshocks for a tachycardia that is well tolerated and could be approachedwith a gentler termination modality, e.g. anti-tachycardia pacing.

FIG. 60 shows a patient 103 with an ICD 2380 which has a transmittingand receiving device. ICD 2380 communicates with transmitting andreceiving device 2384 in central station 300 via the transmitting andreceive device in a nearby control unit 2382. The nearby control unitallows the transmitter within the ICD to use minimal power, and therebyconserve its batteries. The transmitter within the ICD would be in astand-by mode until the ICD detected a potentially abnormal heartrhythm. The rhythm would then be transmitted to the MP in the CS via thecontrol unit. The MP could decide whether to let the ICD make its owndecision, or he could over-ride the decision. Means could be provided tolet the MP preview the ICD decision. The MP could communicate with thepatient either by telephone or other means, to determine theappropriateness of therapy which is either more aggressive or lessaggressive than is programmed in the ICD. In one embodiment of theinvention, the MP could reprogram ICD 2380 to more appropriate settings,based on the event. The MP could notify the patient's physician, whocould participate in decision making such as reprogramming. The MP couldcause the ICD to deliver therapy for a non-life threatening event at atime when the victim is asleep, such determination being made by the MPafter speaking with the victim, or using other communication means.

8.7 Defibrillation Using Two or More Different Shocks in One Victim

FIG. 61 shows a portable unit 2406 which contains two defibrillationcircuits 2408A and 2408B. The output of defibrillation circuit 2408A isapplied to the victim via electrode pads 2404A and 2404B. The output ofdefibrillation circuit 2408B is applied to the victim via electrode pads2400A and 2400B. The waveform and amplitude of each defibrillator iscontrolled by circuits 2410A and 2410B, both of which are controlled bycontrol unit 2410. The MP 301 in the CS 300 controls unit 2410 viatransmitting and receiving devices 2414 in the CS and 2412 in the PU.The waveform, amplitude and timing parameters selected by the MP fordefibrillator 2408A may be the same as or different from those selectedfor 2408B. The electrodes through which the output of 2408A is appliedmay be entirely the same as, entirely different from, or have some butnot all the same constituents as the electrodes through which the outputof 2408B is applied. There may be more than two defibrillators throughwhich energy is applied.

8.8 Monitoring Adequacy of Ventilation During Resuscitation UsingPressure and/or Flow Monitoring

FIG. 62 shows a means for using the PU 104 to monitor and transmit airpressure and air flow information to the MP in the CS 300 (see Section4.3.2.2). A tightly fitting mask 2420 is applied to the victim withtubing 2422 that extends to a source of compressed air within the PU. Anair flow sensing device 2426 and/or an air pressure sensing device 2424is contained within the tubing, the mask or the PU. Cables 2428A and2428B send the information from their respective transducers to the PUmicroprocessor, after which the information is encoded and sent to theMP in the CS. The information can be used to assess the presence andadequacy of spontaneous respiration. It can be used to assess whetherthe mask has been applied appropriately so that its outer border isproperly applied to the victim and forms a seal. If a hand-pumpedventilation “bag,” as is known in the art, is used to ventilate thevictim, the flow and pressure information can be used to assess whetherthe rate and depth of bag compression is appropriate. The mask may bestored in the miscellaneous section 177 of the PU tool-kit (FIG. 7A).The ventilation bag would be stored nearby or brought by the EMT. Thegas with which the victim is ventilated need not be pure air;supplemental oxygen may be admixed.

8.9 Monitoring Adequacy of Ventilation During Resuscitation UsingTransthoracic Impedance

Since the resistance of air is greater than that of body fluids, theresistance across the chest when the lungs are inflated is greater thanwhen they are deflated. This means may be used to monitor respiratorystatus. FIG. 63 shows a victim 102 with five electrode pad 204B on hischest. A portable unit is attached to the pad via cable 222. The unitcontains a transmitting and receiving apparatus 2412 for communicatingwith such apparatus 2414 within the CS. This PU contains a control unitwhich intermittently causes impedance measuring unit 2440 to measure thetransthoracic impedance. The data from this unit is sent to the MP. Theunit also contains ECG monitoring apparatus 2438 and defibrillatingapparatus 2409. The latter is controlled remotely by MP 301.

Appendix 1 Voice Prompt Menu I) Introductory Statements Menu

A) You've reached the Central Station. Can you hear this?

B) Because you couldn't hear me, I've switched to a computer-assistedvoice. Can you hear me now?

C) Please speak louder.

D) I can hear you, so feel free to speak or answer at any time.

E) Would you like me to speak louder?

F) If, at any point, you don't hear me well, or if you would like me torepeat anything, please let me know.

G) Please pick up the telephone on the right side of this unit. We'llhear each other more clearly when you use it.

H) A text version of the voice prompts that you are hearing is appearingsimultaneously on the left (or right) video screen.

I) Please look at the video screen on the left (or right) for furtherwritten instructions.

J) I can't hear you, so please answer my questions by selecting a choiceon the touch sensitive video screen on the right (or left).

K) If you touch “KEYBOARD” on the touch sensitive screen, a standardkeyboard will appear which will allow you to send me a text message.

L) Communication with the Central Station is not possible at thismoment. Your unit's on-board computer will provide you furtherinstructions. Meanwhile, further attempts will be made to link youdirectly to the Central Station.

II) Event Description Menu

A) Please describe the event.

B) Did the victim lose consciousness?

C) Did you witness the event?

D) Are there any witnesses to the event?

E) How many minutes have passed since the start of the event?

F) (If victim is conscious:) Is the victim complaining of chest pain?

G) (If victim is conscious:) Is the victim complaining of shortness ofbreath?

H) Can you tell if the victim breathing?

I) Is there anyone there who knows the victim?

J) Do we know if the victim takes medication?

K) Can you or anyone tell me what medications the victim is taking?

L) Do you know if the victim is diabetic?

M) Was alcohol involved in this incident?

N) Was there a physical injury to the victim?

O) Does the victim have a medical alert bracelet or necklace?

P) I know this is a difficult situation for you, but please try to calmdown.

Q) Please speak a little more slowly.

R) Please repeat your last statement.

S) Please speak louder.

III) Lock Release Menu

A) You can't remove the portable unit from the wall until I release alock.

B) Please do not attempt to remove the portable unit at this time.

C) Your picture has been taken and transmitted to the Central Station,which will allow us to identify you, if you tamper with this unit.

D) To remove the portable unit from the wall, grasp the two handles andpull the unit towards your body.

E) Once the unit has been removed please carry it to the victim's side.

F) During your trip to the victim's side, I'll attempt to speak with youabout other details of the event. If you can't hear me, don't worry orstop; I'll finish the conversation when you get to the victim.

G) To unlock the unit from its wall mounting, you'll need to use thecombination lock on the unit's left side.

H) Set the front (red) wheel at ‘6’. Set the second (blue) wheel at ‘2’.Set the third (white) wheel at ‘8’. Set the back (green) wheel at ‘5’.

IV) Trip to Victim Menu

A) Can you hear me?

B) Can you hear me now?

C) Please speak louder.

D) It's hard to speak while your carrying the unit; We can continue theconversation when you arrive at the victim's side.

E) Please tell me more about the event.

F) When we get to the victims side, place the box on the ground as nearto the victim as possible. The victim's left side, near the chest, isbest. Gently put the unit down so that the side with the screens facesupwards.

G) Once you've placed the unit on the ground, the tool kit door willopen. Inside you'll see various items that you can use to help me findout what's going on and help the victim.

H) I've called your local 9-1-1. Trained personnel are on the way. Inthe meantime you and I can get started.

I) Each moment is precious in this sort of situation, so we'll want tomove as quickly as possible.

J) Have you had any experience with the administration of first aid?

K) Please describe your experience.

L) Don't be concerned about that [your inexperience].

M) I'm an expert in the management of this sort of emergency situation.I'm going to instruct you in some simple steps which require no priorexperience. I'll figure out what's going on and make any neededdecisions.

V) On Arrival Menu

A) Can you hear me?

B) Can you hear me now?

C) Please speak louder.

D) Place the box on the ground as near to the victim as possible. Thevictim's left side, near the chest, is best. Gently put the unit down sothat the side with the screens faces upwards.

E) Is the victim conscious?

F) When the box rests on the ground, the tool-kit door will release.Open it all the way so that you can easily see its contents.

G) It may be easier for us to communicate if you use the headset in thetool compartment. Please try this now.

H) It seems that communicating without the headset worked just as well?Do you agree?

I) Let's go back to communicating without the headset.

J) Notice the video camera. It is on a flexible arm which I am nowextending. Please grasp this arm and point it in the direction of thevictim. You can tell when you have the correct orientation by checkingyour video screen.

K) We'll need to attach a special pad to the victim's chest which willallow me to diagnose and treat the patient electrically.

L) You'll need to remove any clothing covering the victim's chest so wecan place an electrical pad directly on his or her skin.

M) There is a scissors in the tool compartment if you need it.

N) Please do this as quickly as possible.

O) Is a telephone jack within twenty five feet of the box?

P) Please remove the telephone wire from the lower left hand corner ofthe tool-kit and plug it into the telephone jack.

VI) Attach Pad and Peripherals Menu

Note: Voice prompts A-O refer to the initial application ofpacing/defibrillator pads to the victim's chest.

A) Look at the top row of the tool-kit. Please peel off the cover marked“5 Electrode Pad—Standard Version,” and remove the pad from thetool-kit.

B) Look at the second row from the top of the tool-kit. Please peel offthe cover marked “5 Electrode Pad—With Cutout Section” and remove thepad from the tool-kit.

C) Look at the third row from the top of the tool-kit. Please peel offthe cover marked “32 Electrode Pad” and remove the pad from thetool-kit.

D) Look at the fourth row from the top of the tool-kit. Please peel offthe cover marked “Single Electrode Pads” and remove all of them from thetool-kit.

E) Look at your video screen to see how we're going to orient the pad onthe victim's chest.

F) Look at your video screen to see how we're going to orient the padson the victim's chest.

G) Look at your video screen. I'm going to mark the correct pad positionand orientation in red.

H) Look at your video screen. You'll see a cartoon showing the correctpad placement and orientation

I) Before applying the pad, we must be sure that the area to which it isapplied is bare; Please do so.

J) Before applying the pad, we must peel the plastic back off of it.Once you do this, you'll expose an adhesive surface.

K) Try to keep the adhesive back of the pad from coming in contact withanything but the patient.

L) Apply the pad so that the adhesive surface faces the patient.

M) Try to apply the pad so that it is properly positioned and orientedupon first contacting the patient.

N) Try to apply the pad from left to right so that there are no bubbles,or areas where the pad fails to make contact with the victim's skin.

O) I'd like to be able to look at how you've placed the pad, but you are(or someone is) standing between the video camera and the victim. Pleaseallow me an unobstructed view. Note: Voice prompts P—AA are used whenthe system detects high pad impedance, suggesting inadequate contactbetween pad and victim's skin.

P) Please run your hand over all areas of the pad, pressing down firmlyto assure that the pad makes good contact.

Q) Please press down firmly over the area of the pad that I've marked onthe video screen.

R) Please press down firmly over the side of the pad marked “Victim'sLeft”.

S) Please press down firmly over the side of the pad opposite “Victim'sLeft”.

T) Please press down firmly over the side of the pad marked “Victim'sRight”.

U) Please press down firmly over the top half of the pad.

V) Please press down firmly over the bottom half of the pad.

W) Please press down firmly over the center of the pad.

X) Please apply each individual pad in the position indicated on thescreen. They are numbered and color coded to help you.

Y) Please press down firmly over the red pad (or the pad with a ‘1’ onit).

Z) Please press down firmly over the white pad (or the pad with a ‘2’ onit).

AA) Please press down firmly over the blue pad (or the pad with a ‘3’ onit).

Note: In the case of multiple single pads, similar prompts involvingadditional pads (e.g. a fourth pad) are possible. This holds true ineach of the instances where prompts are listed referring to pads ‘1,’‘2’ or ‘3.’

Note: Voice prompts AB—BM refer to situations where the enabler is askedto either reposition a pad or pads, or change pad systems. Such requestsmight occur in the event of one or more unsuccessful defibrillation orpacing attempts. Voice prompts AB—AV ask the enabler to reposition apad.

AB) Please remove the pad and reposition it as I've shown on the screen.

AC) Please remove the pad and reposition it so that it lies furthertowards the victim's left.

AD) Please remove the pad and reposition it so that it lies furthertowards the victim's right.

AE) Please remove the pad and reposition it so that it lies higher up,that is, nearer to the victim's neck.

AF) Please remove the pad and reposition it so that it lies lower down,that is, further from the victim's neck.

AG) Please remove the pad and re-apply it so that it covers the victimevenly, that is, without any bumps or elevations.

AH) Please remove the red pad (or the pad with a ‘1’ on it), andreposition it further towards the victim's left.

AI) Please remove the red pad (or the pad with a ‘1’ on it), andreposition it further towards the victim's right.

AJ) Please remove the red pad (or the pad with a ‘1’ on it) andreposition it further up on the victim, that is, towards his or herneck.

AK) Please remove the red pad (or the pad with a ‘1’ on it) andreposition it further down on the victim, that is, towards his or herfeet.

AL) Please remove the red pad (or the pad with a ‘1’ on it) andreposition it as shown on your video screen.

AM) Please remove the white pad (or the pad with a ‘2’ on it) andreposition it further toward the victims left.

AN) Please remove the white pad (or the pad with a ‘2’ on it) andreposition it further toward the victim's right.

AO) Please remove the white pad (or the pad with a ‘2’ on it) andreposition it further up on the victim, that is, towards his or herneck.

AP) Please remove the white pad (or the pad with a ‘2’ on it) andreposition it further down on the victim, that is, towards his or herfeet.

AQ) Please remove the white pad (or the pad with a ‘2’ on it) andreposition it as shown on your video screen.

AR) Please remove the blue pad (or the pad with a ‘3’ on it) andreposition it further towards the victim's left.

AS) Please remove the blue pad (or the pad with a ‘3’ on it) andreposition it further towards the victim's right.

AT) Please remove the blue pad (or the pad with a ‘3’ on it) andreposition it further up on the victim, that is, towards his or herneck.

AU) Please remove the blue pad (or the pad with a ‘3’ on it) andreposition it further down on the victim, that is, towards his or herfeet.

AV) Please remove the blue pad (or the pad with a ‘3’ on it) andreposition it as shown on your video screen.

Note: Voice prompt AW refers to a situation where one pad system needsto be replaced with a different one. This prompt is likely to befollowed by one of prompts VI-A, VI-B, VI-C or VI-D.

AW) We need to switch pads. Please remove the pad that you previouslyapplied to the chest.

Note: Voice prompts AX-BM refer to a situation where a variation on theusual defibrillation pathway is to be attempted. In this case,instructions are given for application of a pad to the victim's back.

AX) We'll need to reposition one of the round pads to the victim's back.

AY) The easiest way to do this is to roll the victim just enough toexpose the area we need.

AZ) We'll want to roll the victim towards you.

BA) We'll want to roll the victim away from you.

BB) If there is someone at the scene who can help you with this, pleaseask them to help.

BC) As we did before, we'll need to apply the pad to bare skin.

BD) There is a scissors in the tool compartment if you need it.

BE) Please remove the red pad (or the pad with a ‘1’ on it), andreposition it on the victim's back, beneath the right shoulder blade.

BF) Please remove the red pad (or the pad with a ‘1’ on it), andreposition it on the victim's back beneath, the left shoulder blade.

BG) Please remove the red pad (or the pad with a ‘1’ on it) andreposition it on the victim's back, as shown on your video screen.

BH) Please remove the white pad (or the pad with a ‘2’ on it) andreposition it on the victim's back, beneath the right shoulder blade.

BI) Please remove the white pad (or the pad with a ‘2’ on it) andreposition it on the victim's back, beneath the left shoulder blade.

BJ) Please remove the white pad (or the pad with a ‘2’ on it) andreposition it on the victim's back, as shown on your video screen.

BK) Please remove the blue pad (or the pad with a ‘3’ on it) andreposition it on the victim's back, beneath the right shoulder blade.

BL) Please remove the blue pad (or the pad with a ‘3’ on it) andreposition it on the victim's back, beneath the left shoulder blade.

BM) Please remove the blue pad (or the pad with a ‘3’ on it) andreposition it on the victim's back, as shown on your video screen.

Note: Voice prompts BN-BV refer to a situation where one of the alreadyconnected pad(s) needs to be replaced. This might occur if a pad isdamaged or is incorrectly applied.

BN) Look at the fifth row from the top of the tool-kit. Please peel offthe cover marked “Spare Pads.”

BO) Please remove the pad marked “5 Electrode Pad—Standard Version” fromthe “Spare Pads” section that you just opened.

BP) Please remove the pad marked “5 Electrode Pad—With Cutout Section”from the “Spare Pads” section that you just opened.

BQ) Please remove the pad marked “32 Electrode Pad” from the “SparePads” section that you just opened.

BR) Please remove the cluster of pads marked “Single Electrode Pads”from the section that you just opened.

BS) I'm going to tell you how to attach the Spare Pad that you justremoved from the tool-kit. You'll need gently pull the cable of the padthat you've been using out of the tool-kit.

BT) You'll see a connector which connects the pad you've been using tothe box. By wiggling its two parts, you can disconnect them.

BU) Now insert the (green) connector of the replacement pad that youjust took out of the “Spare Pads” section into the (orange) connectorwhich you just freed up.

BV) Push the two connectors together firmly until you hear a click.

Note: Voice prompts BW-CR refer to the application and adjustment of“mini-pads.”

BW) Look at the bottom row of the tool-kit. Peel of the cover marked“Miscellaneous” and remove the package of four multicolored pads.

BX) Open the package. We're going to apply one pad to each arm and leg.

BY) Apply the red pad marked ‘RA’ to the right arm. Peel the plasticbacking off of the pad just before you apply it. The sticky side is theone that must touch the victim's skin.

BZ) Apply the red pad marked ‘RA’ to the right hand. Peel the plasticbacking off of the pad just before you apply it. The sticky side is theone that must touch the victim's skin.

CA) In the same manner, apply the white pad marked ‘LA’ to the left arm.

CB) In the same manner, apply the white pad marked ‘LA’ to the lefthand.

CC) Now apply one blue pad marked ‘LEG’ to each leg.

CD) Now apply one blue pad marked ‘LEG’ to each foot.

CE). Look at your video screen. I'm going to mark the correct mini-padposition in red.

CF) Look at your video screen. You'll see a cartoon showing the correctmini-pad placement.

CG) Please make sure that each mini-pad is applied directly to thevictim's bare skin.

CH) Please make sure that the arm or hand mini-pads are applied to thevictim's bare skin. You may, however, apply the blue leg mini-pads to astocking.

CI) Please press down firmly over each of the mini-pads.

CJ) Please press down firmly over the red mini-pad.

CK) Please press down firmly over the white mini-pad.

CL) Please press down firmly over the blue mini-pad on the right leg.

CM) Please press down firmly over the blue mini-pad on the left leg.

CN) Please remove the red, right arm mini-pad and position it as I'veshown on the video screen.

CO) Please remove the white, left arm mini-pad and position it as I'veshown on the video screen.

CP) Please remove the blue, right leg mini-pad and position it as I'veshown on the video screen.

CQ) Please remove the blue, left leg mini-pad and position it as I'veshown on the video screen.

CR) My information shows that the victim requires therapy which can onlybe accomplished with pads which must be applied to the chest.

Note: Voice prompts CB-CE refer to the application of apparatus to thevictim for monitoring hemodynamic and respiratory status.

CS) Please take the device from the lower right corner of the tool-kitand place it on one of the victim's fingers.

CT) Please move the finger device to a different one of the victim'sfingers

CU) Please look at the video screen for instructions on how to place thefinger device.

CV) Please remove the blood pressure device from the right side of thetool-kit and apply it as shown on the video screen.

VII) Shock/Pace Menu

A) The victim has a life threatening heart rhythm problem and I'm goingto administer a shock. Please make sure that neither you nor anyone elseis now touching the victim.

B) I'm going to administer another shock now. Please make sure that noone is touching the victim.

C) A momentary twitch or jerk of the body when a shock is administeredis normal.

D) The victim's heartbeat is too slow. I'm going to try to speed it upby a technique called pacing.

E) You may observe some twitching of the victim's chest muscles while Iperform the pacing. This is normal.

F) I'd like you to try to find out if the victim has regainedconsciousness.

G) Please try speaking loudly to the victim.

VIII) Miscellaneous Menu

A) The victim's heart rhythm is now normal. You did a good job!

B) Trained emergency personnel are on the way and should be arrivingsoon.

C) Trained emergency personnel are on the way but they will need aboutfive minutes to get here.

D) Trained emergency personnel are on the way but they will need aboutten minutes to get here.

E) Trained emergency personnel are on the way but they will need aboutfifteen minutes to get here.

F) Trained emergency personnel are on the way but they will need abouttwenty minutes to get here.

G) I have been unable to reach any nearby emergency personnel, but I amcontinuing to try.

H) Unfortunately, our resuscitation has been unsuccessful up to thispoint.

I) If we are not successful over the next few minutes, I'm going to askyou to stop your efforts.

J) I'm going to ask you to stop your efforts at this time. We have doneall that we can.

K) Please insert all free items except the pad into the tool-kit andclose the tool-kit door.

L) We would be most appreciative if you can now return the unit to theplace where you got it.

M) Please gently slide the unit back onto the shelf. Keep pushing untilyou hear the lock engage.

N) Thank you for helping. You did a fine job.

Note: Voice prompts 0-AG refer to CPR administration.

O) The victim's heart rhythm is now normal but he or she would benefitfrom CPR (cardiopulmonary resuscitation). Have you had any CPR training?

P) Apparatus to assist in ventilating the victim is located in themiscellaneous compartment of the tool-kit.

Q) You may begin CPR now. The pad(s) does not need to be removed fromthe chest to do this.

R) Is there anyone on the scene who can assist you with CPR?

S) I'm going to show you a very brief video about CPR.

T) Once you get started, I'll provide additional advice.

U) You're doing fine but you need to compress the chest harder.

V) You're doing fine but you don't need to compress the chest that hard.

W) You're doing fine but you need to compress the chest faster.

X) You're doing fine but you don't need to compress the chest that fast.

Y) The point where you compress the chest should be a little closer tothe victim's head.

Z) The point where you compress the chest should be a little furtherfrom the victim's head.

AA) Please use two hands when compressing the chest.

AB) Use the heel of your hand, that is, the portion nearest to yourwrist, to compress the chest.

AC) Ventilating the victim more frequently would help.

AD) You can ventilate the victim less frequently.

AE) The victim is now breathing on his or her own. You can stopventilating.

AF) The victim's heart is now beating strongly. You can stop CPR.

AG) The victim requires another shock at this time. You'll need to stopCPR for about five seconds. Please make sure that no one is in contactwith the victim at this time.

Note: Voice prompts AH through AR are for arriving emergency personnel

AH) Please identify yourself.

AI) The video screen shows a log of the events that have just occurred.

AJ) Please indicate what additional information you would like to have.

AK) If you would like, we can transfer control of this device directlyto you. Would you like me to do that?

AL) I'm going to show you a brief instructional video on the use of thisdevice.

AM) I will be available at all times to further instruct you in itsproper use.

AN) We can leave the chest pad in place and easily reconnect it to yourdevice.

AO) Gently pull the cable (between pad and tool-kit) so that more of itcomes out of the tool-kit. You'll see the green and orange connectorswhich attach the pad to the box. By wiggling these two connectors, youcan disconnect them.

AP) You can then attach the pad to any free connector in your box.

AQ) There are adapters in the “Miscellaneous” section of the tool-kit.They may be used to attach the victim's pad to your defibrillator.

AR) We would appreciate your calling our Central Station at800 - - - - - - when you have arrived at your destination so that we maymake arrangements to retrieve our portable unit.

IX) Switch to AED Menu

A) This device has not been able to reach the Central Station, whereexpert medical personnel are available to help you. It will continue totry, and is likely to be successful over the next few minutes.

B) If you are witness to what you believe may be a cardiac arrest, or ifyou are dealing with an unconscious victim, you may use this device. Itwill, with minimal assistance from you, allow for the resuscitation ofsuch a victim. It requires no prior training. It will instruct you withvoice and test messages. To continue, please press the emergency buttonagain, now.

C) To unlock the unit from its wall mounting, you'll need to use thecombination lock on the left side of the unit.

D) Set the front (red) wheel at ‘6’. Set the second (blue) wheel at ‘2’.Set the third (white) wheel at ‘8’. Set the back (green) wheel at ‘5’.

E) To remove the portable unit from the wall, grasp the two handles andpull the unit towards your body.

F) Once the unit has been removed please carry it to the victim's side.

G) Communication with the Central Station has been interrupted. Controlof this device has been transferred to an on-board computer. Thecomputer will instruct you until either communication with the CentralStation is re-established, or until the arrival of emergency personnel.

X) Possible AED Voice Prompts

Note: The following is a list of possible voice prompts, mostly from theprevious menus, which might be used during a situation in which theCentral Station could not be contacted:

From I) Introductory Statements Menu:

-   -   H, L

From IV) Trip to Patient Menu:

-   -   F, G, H, I

From V) On Arrival Menu:

-   -   D, F, G, K, L, M, N

From VI) Attach Pad and Peripherals Menu:

-   -   A-F, H-N, P-Z, AA, CB-CE

From VII) Shock/Pace Menu:

-   -   A, B, C, D, E

From VIII) Miscellaneous Menu:

-   -   A, B, J, L, M, N, P, Q, V, W, Y, Z, AA, AB, AC

From IX) Switch to AED Menu:

-   -   A-G        In addition, the following voice prompts could be utilized        during automatic operation:

A) If the volume is not loud enough for you, please say “louder”, ortouch the box marked “louder” on the touch sensitive video screen on theright (or left).

B) You may use the telephone handset to hear better.

C) If at any point you would like a prompt repeated, please say “repeat”or touch the box marked “repeat” on the touch sensitive screen.

D) The victim's heart rhythm is now normal, but he or she would benefitfrom CPR (cardiopulmonary resuscitation). Have you, or anyone on thescene had training in CPR? Please answer by saying the word “yes” or“no”, or by touching the answer on the touch sensitive video screen onthe right (or left).

Appendix 2 Abbreviations Used

-   Δ Change-   AB Audio Beacon-   AED Automatic External Defibrillator-   AED/P Automatic External Defibrillator/Pacer-   AMP Amplifier-   ATP Anti-Tachycardia Pacing-   AV Atrioventricular-   BP Blood Pressure-   BPM Beats Per Minute-   BW Bandwidth-   COMM Communication-   CONF'N Confirmation-   CPR Cardiopulmonary Resuscitation-   CS Central Station-   DEFIB Defibrillator-   ECG Electrocardiogram-   EMT Emergency Medical Team-   EN Enabler-   FIG. # Figure Number-   FoLanRec Foreign Language Recognition Program-   GPS Global Positioning System-   Hi Shock High Energy Shock-   HS Handshake-   HV High Voltage-   ICD Implantable Cardioverter-Defibrillator-   Interp'r Interpreter-   KYBD Keyboard-   LE Long Echo=confirmation signal #3-   Lo Shock Low Energy Shock-   LOS Line of Sight-   m:ss Minutes:Seconds-   MC Master Counter-   MP Medical Professional-   NG No Good-   NR No Response-   O₂ SAT Oxygen Saturation-   OP Operational-   p/Δ gain apply pressure and/or change gain-   PACER Pacemaker-   PU Portable Unit-   PU-1 First Portable Unit-   PU-2 Second Portable Unit-   PU/SU Portable Unit/Stationary Unit combination-   PW Pulse Width-   PWD Password-   RCVR Receiver-   RF Radio frequency-   SAT Satellite-   SC Screen-   SE Short Echo=confirmation signal #2-   SM Screen Message-   SpeechRec Speech Recognition Program-   SPKR Speaker-   SU Stationary Unit-   SVT Supraventricular Tachycardia-   SYNCH Synchronization-   TELCO Public Telephone Network-   TELEM Telemetry-   Text Pr Text Prompts-   TSS Touch Sensitive Screen-   UC Universal Connector-   VF Ventricular Fibrillation-   VI Victim-   Video Pr Video Prompts-   Video CAM Video Camera-   VLE Very Long Echo=confirmation signal #4-   Voice Pr Voice Prompts-   Voice Re Voice Recognition-   VSE Very Short Echo=confirmation signal #1-   VT Ventricular Tachycardia-   XMTR Transmitter-   % RR Percentage of interval between heartbeats

There has thus been shown and described a novel system for cardiacresuscitation which fulfills all the objects and advantages soughttherefor. Many changes, modifications, variations and other uses andapplications of the subject invention will, however, become apparent tothose skilled in the art after considering this specification and theaccompanying drawings which disclose the preferred embodiments thereof.All such changes, modifications, variations and other uses andapplications which do not depart from the spirit and scope of theinvention are deemed to be covered by the invention, which is to belimited only by the claims which follow.

1-377. (canceled)
 378. A cardiac monitoring and external defibrillation system which allows an untrained human enabler immediate access to a medical professional who can and will remotely monitor, diagnose and treat a victim of medical emergency at one of a plurality of remote sites, said system comprising, in combination: (a) a central station comprising: (1) a first display device for displaying cardiac information from a victim for evaluation by said medical professional; (2) a first input device, responsive to said medical professional, for producing control signals for controlling operation of emergency cardiac monitoring and external defibrillation apparatus at one of said remote sites and the application of a defibrillation pulse to said victim at said one site; and (3) a first transmitting/receiving (T/R) device, coupled to said first display device and said first input device, for electronic communication with emergency cardiac monitoring and defibrillation apparatus disposed at each of a plurality of remote sites; and (b) emergency cardiac monitoring and external defibrillation apparatus disposed at each of a plurality of remote sites, each said apparatus comprising a portable unit including: (1) a second transmitting/receiving (T/R) device for electronic communication with said first T/R device of said central station; (2) a master control unit, connected to said second T/R device, for controlling the operation of said cardiac monitoring and defibrillation apparatus, said control unit having a plurality of operating states selected from the group consisting of: (i) enable remote control by medical professional; (ii) enable automatic local control; and (iii) enable local control by emergency medical personnel; (3) a defibrillator circuit, having a control input coupled to said second T/R device and said master control unit, for generating a defibrillation pulse at a defibrillator circuit output in response to a defibrillation control signal received at said defibrillator circuit control input; (4) a logic device for automatic local control of the portable unit, coupled to said second T/R device, to said master control unit and to the control input of said defibrillator circuit, for automatically producing a second defibrillation control signal for controlling the application of said defibrillation pulse to said victim in response to electrocardiogram (ECG) signals received from said victim; (5) an electrocardiogram (ECG) circuit, having an ECG circuit output, coupled to said second T/R device and to said logic device, and having an ECG electrode input; (6) a plurality of contact electrodes, adapted to be placed by a nearby enabler upon a chest wall of said victim, said plurality of contact electrodes being adapted to be arranged at separate locations on said chest wall for the receipt of ECG signals from said victim and for application of said defibrillation pulse to said victim; (7) a connecting cable having a plurality of electric wires for connecting each of said contact electrodes to at least one of (i) said ECG electrode input and (ii) said defibrillator output; (8) a second display device, coupled to said ECG circuit output for display of said ECG signals; and (9) a second input device, coupled to said control input of said defibrillator circuit, for locally activating defibrillation; wherein (1) said ECG signals are transmitted from selected ones of said contact electrodes via said ECG circuit to said central station and displayed on said first display unit for evaluation by said medical professional, (2) said first defibrillation control signal may be transmitted from said central station to said control input of said defibrillator circuit and (3), in response thereto, said defibrillator circuit generates said defibrillation pulse for application to at least one of said contact electrodes for resuscitation of said victim; and wherein said master control unit selects the operating state of said portable unit at the remote site under control of said medical professional at said central station; and wherein, if enabled by said medical professional, (4) said ECG signals are transmitted from selected ones of said contact electrodes via said ECG circuit and displayed on said second display unit for evaluation by said emergency medical personnel, (5) said first defibrillation control signal may be transmitted from said second input device said control input of said defibrillator circuit, and (6), in response thereto, said defibrillator circuit generates said defibrillation pulse for application to at least one of said contact electrodes for resuscitation of said victim.
 379. A cardiac monitoring and external defibrillation system which allows an untrained human enabler immediate access to a medical professional who can and will remotely monitor, diagnose and treat a victim of medical emergency at one of a plurality of remote sites, said system comprising, in combination: (a) a central station comprising: (1) a display device for displaying cardiac information from a victim for evaluation by said medical professional; (2) a first input device, responsive to said medical professional, for producing a first defibrillation control signal for controlling the application of a defibrillation pulse to said victim; (3) a second input device, responsive to a medical professional, for producing a defibrillation command signal, for initiating the automatic application of a defibrillation pulse to said victim; and (4) a first transmitting/receiving (T/R) device, coupled to said display device and to said first and second input devices, for electronic communication with emergency cardiac monitoring and defibrillation apparatus disposed at each of a plurality of remote sites; and (b) emergency cardiac monitoring and external defibrillation apparatus disposed at each of a plurality of remote sites, each said apparatus comprising a portable unit including: (1) a second transmitting/receiving (T/R) device for electronic communication with said first T/R device of said central station; (2) a logic device for automatic control of the portable unit, coupled to the second T/R device, for automatically producing a second defibrillation control signal for controlling the application of a defibrillation pulse to said victim, upon receipt of a defibrillation command signal from said central station, in response to electrocardiogram (ECG) signals received from said victim; (3) a defibrillator circuit, having a control input coupled to said second T/R device and to said logic device, for generating a defibrillation pulse at a defibrillator circuit output in response to a either a first or a second defibrillation control signal received at said defibrillator circuit control input; (4) an electrocardiogram (ECG) circuit, having an ECG circuit output, coupled to said second T/R device and to said logic device, and having an ECG electrode input; (5) a plurality of contact electrodes, adapted to be placed by a nearby enabler upon a chest wall of said victim, said plurality of contact electrodes being adapted to be arranged at separate locations on said chest wall for the receipt of ECG signals from said victim and for application of said defibrillation pulse to said victim; and (6) a connecting cable having a plurality of electric wires for connecting each of said contact electrodes to at least one of (i) said ECG electrode input and (ii) said defibrillator output; wherein (1) said ECG signals are transmitted from selected ones of said contact electrodes via said ECG circuit to said central station for evaluation by said medical professional, (2) said logic device includes means for analyzing said ECG signals and produces a signal representing the result of the analysis, said analysis signal being transmitted to said central station via said second and first T/R devices, respectively, for display by said display device for the consideration by said medical professional, whereby said medical professional is able compare the analysis of said logic device with his/her own medical judgment; (3) said first defibrillation control signal may be transmitted from said central station to said control input of said defibrillator circuit and, in response thereto, said defibrillator circuit generates said defibrillation pulse for application to at least one of said contact electrodes for resuscitation of said victim; and (4) said defibrillation command signal may be sent from said central station to said logic device at said remote site and, in response thereto, said defibrillator circuit is responsive to said second defibrillation control signal generated by said logic device to generate said defibrillation pulse for application to said at least one contact electrode for resuscitation of said victim, thereby allowing said medical professional to take advantage of the analysis by said logic device.
 380. A cardiac monitoring and external defibrillation and cardiac pacing system which allows an untrained human enabler immediate access to a medical professional who can and will remotely monitor, diagnose and treat a victim of medical emergency at one of a plurality of remote sites, said system comprising, in combination: (a) a central station comprising: (1) a display device for displaying cardiac information from a victim for evaluation by said medical professional; (2) at least one first input device, responsive to said medical professional, for producing a defibrillation control signal for controlling the application of a defibrillation pulse to said victim; (3) at least one second input device, responsive to said medical professional, for producing a cardiac pacing control signal for controlling the application of one or more cardiac pacing pulses to said victim; and (4) a first transmitting/receiving (T/R) device, coupled to said display device and to said first and said second input devices, for electronic communication with emergency cardiac monitoring, defibrillation and cardiac pacing apparatus disposed at each of a plurality of remote sites; and (b) emergency cardiac monitoring and external defibrillation and cardiac pacing apparatus disposed at each of a plurality of remote sites, each said apparatus comprising a portable unit including: (1) a second transmitting/receiving (T/R) device for electronic communication with said first T/R device of said central station; (2) a defibrillator circuit, having a defibrillation control input coupled to said second T/R device, for producing a defibrillation pulse at a defibrillator circuit output in response to a defibrillation control signal received at said defibrillation control input; (3) a cardiac pacing circuit, having a pacing control input coupled to said second T/R device, for producing said one or more cardiac pacing pulses at a pacing circuit output in response to a cardiac pacing control signal received at said pacing control input; (4) a logic device, coupled to the second T/R device and to the control input of said defibrillator circut and to the pacing control input of said cardiac pacing circuit, for automatically producing at least one of a second defibrillation control signal for controlling the application of said defibrillation pulse to said victim, and a second cardiac pacing control signal for controlling the application of said cardiac pacing pulses to said victim, in the absence of proper communication between said first T/R device and said second T/R device, in response to electrocardiogram (ECG) signals received from said victim; (5) an electrocardiogram (ECG) circuit, having an ECG circuit output, coupled to said second T/R device and to said logic device, and an ECG electrode input; (6) a plurality of contact electrodes, adapted to be placed by a nearby enabler upon a chest wall of said victim, said plurality of contact electrodes being adapted to be arranged at separate locations on said chest wall for (1) the receipt of ECG signals from said victim; (2) for application of said defibrillation pulse to said victim and (3) for application of said one or more pacing pulses to said victim; and (7) a connecting cable having a plurality of electric wires for connecting each of said contact electrodes to at least one of (i) said ECG electrode input; (ii) said defibrillator output and (iii) said cardiac pacing output; whereby (1) said ECG signals may be transmitted from selected ones of said contact electrodes via said ECG circuit to said central station for evaluation by said medical professional; (2) said defibrillation control signal and said cardiac pacing control signal may be transmitted from said central station to said defibrillation control input and said pacing control input, respectively; and (3) in response thereto, said defibrillation pulse may be transmitted from said defibrillator output or said cardiac pacing pulses may be transmitted from said cardiac pacing output to selected ones of said contact electrodes for resuscitation of said victim.
 381. Multiple-pin electrical connector apparatus capable of sensing when and which two specific connector elements are connected together, said connector apparatus comprising, in combination: (a) a first connector element having a plurality of first pins each adapted to be electrically connected to a first electric circuit element; (b) a plurality of second connector elements, each having a plurality of second pins each adapted to be connected to a respective one of said first pins of said first connector element and adapted to be electrically connected to a second electric circuit element, each second connector element having a different pair of said second pins electrically connected together to create a low electrical resistance path between them; and (c) logic means, coupled to at least three first pins of said first connector element, for determining which pair of first pins of said first connector element have a low resistance path between them when said two connector elements are coupled together, thereby to determine which one of said plurality of second connector elements is connected to said first connector element.
 382. The apparatus defined in claim 381, further comprising a first circuit element connected to some of said first pins of said first connector element and a second circuit element connected to some of said second pins of said second connector element, and wherein said first circuit element comprises a defibrillator circuit and said second circuit element comprises a plurality of contact electrodes for application to a chest wall of a victim of medical emergency.
 383. The electrical connector defined in claim 381, further comprising a cardiac monitoring and external defibrillation system which allows an untrained human enabler immediate access to a medical professional who can and will remotely monitor, diagnose and treat a victim of medical emergency at one of a plurality of remote sites, said system comprising, in combination: (a) a central station comprising: (1) a display device for displaying cardiac information from a victim for evaluation by said medical professional; (2) a first input device, responsive to said medical professional, for producing a first defibrillation control signal for controlling the application of a defibrillation pulse to said victim; and (3) a first transmitting/receiving (T/R) device, coupled to said display device and said first input device, for electronic communication with emergency cardiac monitoring and defibrillation apparatus disposed at each of a plurality of remote sites; and (b) emergency cardiac monitoring and external defibrillation apparatus disposed at each of a plurality of remote sites, each said apparatus comprising a portable unit including: (1) a second transmitting/receiving (T/R) device for electronic communication with said first T/R device of said central station; (2) a defibrillator circuit, having a control input coupled to said second T/R device, for generating a defibrillation pulse at a defibrillator circuit output in response to a defibrillation control signal received at said defibrillator circuit control input; (3) an electrocardiogram (ECG) circuit, having an ECG circuit output, coupled to said second T/R device, and having an ECG electrode input; (4) a plurality of contact electrodes, adapted to be placed by a nearby enabler upon a chest wall of said victim, said plurality of contact electrodes being adapted to be arranged at separate locations on said chest wall for the receipt of ECG signals from said victim and for application of said defibrillation pulse to said victim; and (5) a connecting cable having a plurality of electric wires for connecting each of said contact electrodes, via said electrical connector, to at least one of (i) said ECG electrode input and (ii) said defibrillator output; whereby (1) said ECG signals may be transmitted from said contact electrodes via said connecting cable and said electrical connector to said ECG circuit and from thence to said central station, (2) said first defibrillation control signal may be transmitted from said central station to said control input of said defibrillator circuit and (3), in response thereto, said defibrillator circuit may generate said defibrillation pulse for application to at least one of said contact electrodes, for resuscitation of said victim, via said electrical connector and said connecting cable.
 384. A flexible, semi-rigid pad having a substantially flat surface adapted to be placed upon the chest wall of a victim of medical emergency for establishing an electrical connection with a plurality of points on said chest wall, said pad comprising, in combination: (a) a pad substrate of flexible, semi-rigid material, said substrate having a substantially flat surface which is substantially conformable to the chest wall of said victim; (b) at least three contact electrodes disposed in spaced relation on said surface, said contact electrodes being electrically insulated from each other and adapted to make contact with the chest wall of said victim; (c) a detection device, connected to said contact electrodes, for determining the resistance between respective pairs of said electrodes when said pad is attached to said chest wall of said victim, thereby to determine whether the resistance between said chest wall and said respective pairs of electrodes are sufficiently low for the transmission of electric current to effect at least one of monitoring and treatment of said victim; and (d) a defibrillator circuit connected to said contact electrodes, whereby said detection device determines which pair of electrodes, if any, are usable as contact electrodes for said defibrillator circuit.
 385. The system defined in claim 384, wherein said detection device includes means for applying a voltage between one electrode and at least one other electrode and measuring the current flow.
 386. The system defined in claim 385, wherein said voltage applying means applies a voltage between said one electrode and all other electrodes.
 387. The system defined in claim 386, wherein said voltage applying means applies a voltage between each electrode, in turn, and all of the other respective electrodes.
 388. A cardiac monitoring and external defibrillation system which allows an untrained human enabler immediate access to a medical professional who can and will remotely monitor, diagnose and treat a victim of medical emergency at one of a plurality of remote sites, said system comprising, in combination: (a) a central station comprising: (1) a display device for displaying cardiac information from a victim for evaluation by said medical professional; (2) at least one first input device, responsive to said medical professional, for producing a defibrillation control signal for controlling the application of a defibrillation pulse to said victim; (3) at least one second input device, responsive to said medical professional, for transmitting instructional information to said enabler;; and (4) a first transmitting/receiving (T/R) device, coupled to said display device and to said first and said second input devices, for electronic communication with emergency cardiac monitoring and defibrillation apparatus disposed at each of a plurality of remote sites; and (b) emergency cardiac monitoring and external defibrillation apparatus disposed at each of a plurality of remote sites, each said apparatus comprising a portable unit including: (1) a second transmitting/receiving (T/R) device for electronic communication with said first T/R device of said central station; (2) a defibrillator circuit, having a defibrillation control input coupled to said second T/R device, for producing a defibrillation pulse at a defibrillator circuit output in response to a defibrillation control signal received at said defibrillation control input; (3) an instruction receiving device, coupled to said second T/R device, for receiving said instructional information for use by said enabler; (4) an electrocardiogram (ECG) circuit, having an ECG circuit output, coupled to said second T/R device, and having an ECG electrode input; (5) a plurality of contact electrodes, adapted to be placed by a nearby enabler upon a chest wall of said victim, said plurality of contact electrodes being adapted to be arranged at separate locations on said chest wall for (1) the receipt of ECG signals from said victim; (2) for application of said defibrillation pulse to said victim; and (6) a connecting cable having a plurality of electric wires for connecting each of said contact electrodes to at least one of (i) said ECG electrode input; and (ii) said defibrillator; whereby (1) said ECG signals may be transmitted from selected ones of said contact electrodes via said ECG circuit to said central station for evaluation by said medical professional; (2) said defibrillation control signal may be transmitted from said central station to said defibrillation control input and said pacing control input, respectively; and (3) in response thereto, said defibrillation pulse may be transmitted from said defibrillator output to selected ones of said contact electrodes for resuscitation of said victim.
 389. The system defined in claim 388, wherein said second input device includes a microphone and said instruction receiving device includes a speaker, for providing spoken audio instructions to said enabler.
 390. The system defined in claim 388, wherein said instruction receiving device includes an instructional display device, for providing video instructions to said enabler.
 391. The system defined in claim 390, wherein said instruction receiving device further includes means for storing instructional video information, connected to said instructional display device, for causing said instructional display device to display said video information, whereby said medical professional can activate the display of said video information by means of said second input device.
 392. The system defined in claim 391, wherein said instructional video information includes at least one of: (i) instructional information concerning the performance of cardiopulmonary resuscitation; (ii) instructional information concerning the use of said portable unit; and (iii) instructional information concerning the placement of said contact electrodes by said enabler.
 393. The system defined in claim 390, wherein said central station further includes means for storing instructional video information, coupled to said second input device and said first T/R device, for causing said instructional display device to display said video information, whereby said medical professional can activate the display of said video information by means of said second input device.
 394. The system defined in claim 393, wherein said instructional video information includes at least one of: (i) instructional information concerning the performance of cardiopulmonary resuscitation; (ii) instructional information concerning the use of said portable unit; and (iii) instructional information concerning the placement of said contact electrodes by said enabler.
 395. The system defined in claim 390, wherein said central station further includes means for generating instructional video information in substantially real-time, coupled to said second input device, said display device and said first T/R device, for causing said instructional display device to display said video information, said instructional information consisting of at least one of (i) video file information with at least one real-time video annotations by said MP; and (ii) real-time diagrammatic information by said MP.
 396. The system defined in claim 395, wherein said emergency cardiac monitoring and external defibrillation apparatus further comprises a video camera, coupled to said second T/R device for the transmission of video images of said victim to said medical professional, and wherein said instructional video information consists of at least one of: (i) video images of said victim with at least one real-time video annotation by said MP; and (ii) instructional information for said enabler, based on analysis of said victim video image by said MP.
 397. A cardiac monitoring and internal defibrillation and pacing system which allows a patient with an implanted cardiac pacing-defibrillator device immediate access to a medical professional who can and will remotely monitor, diagnose and treat a medical emergency, said system comprising, in combination: (a) a central station comprising: (1) a display device for displaying cardiac information from a patient for evaluation by said medical professional; (2) a first input device, responsive to said medical professional, for producing a first defibrillation control signal for controlling the application of a defibrillation pulse to said patient; and (3) a second input device, responsive to said medical professional, for producing a first pacing control signal for controlling the application of a pacing pulse to said patient; (4) a first transmitting/receiving (T/R) device, coupled to said display device and said first and said second input devices, for electronic communication with emergency cardiac monitoring and defibrillation apparatus disposed at each of a plurality of remote sites; and (b) emergency cardiac monitoring and internal pacing-defibrillation apparatus disposed at each of a plurality of remote sites, each said apparatus comprising a unit implanted in a patient and including: (1) a second transmitting/receiving (T/R) device for electronic communication with said first T/R device of said central station; (2) a defibrillator circuit, having a control input coupled to said second T/R device, for generating a defibrillation pulse at a defibrillator circuit output in response to a defibrillation control signal received at said defibrillator circuit control input; (3) a pacing circuit, having a control input coupled to said second T/R device, for generating at least one pacing pulse at a pacing circuit output in response to a pacing control signal received at said pacing circuit control input; (4) a logic device for automatic control of the implanted unit, coupled to the second T/R device and to the control inputs of said defibrillator circuit and said pacing circuit, for (i) automatically producing a second defibrillation control signal for controlling the application of said defibrillation pulse to said patient in the absence of proper and timely communication between said first T/R device and said second T/R device, in response to electrogram (EGM) signals received from said patient; (ii) automatically producing a second pacing control signal for controlling the application of said at least one pacing pulse to said patient in the absence of proper and timely communication between said first T/R device and said second T/R device, in response to electrogram (EGM) signals received from said patient; (5) an electrogram (EGM) circuit, having an EGM circuit output, coupled to said second T/R device and to said logic device, and having one or more EGM electrode inputs; (6) a plurality of electrodes, adapted to be coupled at separate locations to internal tissue of said patient, for the receipt of EGM signals from said patient and for application of said defibrillation pulse to said patient; and (7) a means for connecting each of said electrodes to at least one of (i) said EGM electrode inputs and (ii) said defibrillator output; whereby (1) said EGM signals may be transmitted from selected ones of said electrodes via said EGM circuit to said central station for evaluation by said medical professional, (2) said first defibrillation control signal may be transmitted from said central station to said control input of said defibrillator circuit and in response thereto, said defibrillator circuit may generate said defibrillation pulse for application to at least one of said electrodes for resuscitation of said patient; and wherein, in the absence of proper and timely communication between said first T/R device and said second T/R device, said defibrillator circuit is responsive to said second defibrillation control signal received from said logic device to generate said defibrillation pulse for application to said at least one electrode for resuscitation of said patient, and (3) said first pacing control signal may be transmitted from said central station to said control input of said pacing circuit and in response thereto, said pacing circuit may generate said at least one pacing pulse for application to at least one of said electrodes for resuscitation of said patient; and wherein, in the absence of proper and timely communication between said first T/R device and said second T/R device, said pacing circuit is responsive to said second pacing control signal received from said logic device to generate said at least one pacing pulse for application to said at least one electrode for resuscitation of said patient.
 398. The system defined in claim 397, further comprising a control unit, adapted for use at the remote site of each implanted unit, said control unit comprising: (1) third transmitting/receiving (T/R) device for electronic communication with said first T/R device of said central station; and (2) fourth transmitting/receiving (T/R) device, coupled to said third T/R device, for electronic communication with said second T/R device of said implanted unit; whereby said implanted unit may communicate with said central station through said control unit.
 399. The system defined in claim 398, wherein said first T/R device and said second T/R device include means for direct duplex communication between them, without transmission through said third T/R device and said fourth T/R device, said communication means being selected from the group consisting of: (i) a wireless transmission link; (ii) a transmission link with wired and wireless segments; and (iii) a transmission link with the Internet and wireless segments.
 400. An audio system comprising: (a) a first input device, arranged at each of at least one first locations, having a first microphone and audio input signal processing means, electrically connected to said first microphone, for producing a first audio signal representing received sound; (b) a sound producing device, arranged at each of said at least one first locations, having a loudspeaker and audio output signal processing means, electrically connected to said loudspeaker, for causing said loudspeaker to produce a sound in response to a test signal; (c) a sound transducer, arranged at a second location remote from said first location, for producing a sound in response to, and represented by, an audio signal; (d) a control device, arranged at said second location, for producing said test signal in response to a manual control input by a human operator; and (e) a first transmitting device, located at each first location, coupled to said audio input signal processing means; (f) a first receiving device, located at each first location, coupled to said audio output signal processing means; (g) a second transmitting device, at said second location and coupled to said control device, for electronic communication with each of said at least one first receiving devices; and (h) a second receiving device, at said second location and coupled to said sound transducer, for electronic communication with each of said first transmitting devices; wherein a human operator may remotely test said audio system by providing a manual input to said control device; thereby (1) transmitting said test signal from said control device at said second location to said sound producing device at said first location; (2) transmitting said first audio signal from said microphone at said first location to said sound transducer at said second location; and (3) listening to said sound transducer at said second location; whereby, following said test signal, the presence and quality of the sound at said second location provides information to the human operator about the quality of said audio system.
 401. The audio system defined in claim 400, further comprising a second input device coupled to said second transmitter, allowing said human operator to select one particular first receiving device, whereby said operator may test the apparatus at one particular first location, in an audio system comprising a plurality of first locations.
 402. The audio system defined in claim 401, further comprising a second microphone coupled to said second transmitting device arranged at said second location for producing a second audio signal representing received sound, said second audio signal being transmitted to said loudspeaker at said first location by said second transmitting device and said first receiving device; whereby said human operator may remotely test the audio system at a first location by listening to said sound transducer at said second location while speaking into said second microphone.
 403. The audio system defined in claim 402, further comprising means for delaying the production of sound by said sound transducer to avoid producing the sound spoken into said second microphone at substantially the same time that said sound is generated by said human operator.
 404. The audio system defined in claim 401, further comprising an audio quality control input device, coupled to said second transmitter, for inputting at least one audio quality control signal, and wherein said audio input signal processing means is further coupled to said first receiving device whereby said operator may (1) adjust the quality of the sound produced by said loudspeaker by inputting a first audio quality control signal which affects signal processing by said audio output signal processing means; and (2) adjust the quality of the sound produced by said sound transducer by inputting a second audio quality control signal which affects signal processing by said audio input signal processing means; thereby allowing said operator at said second location to control sound quality at least one of said first and said second locations by remotely adjusting at least one of said signal processing means at said first location.
 405. The audio system defined in claim 404, wherein said audio quality control signal controls at least one of: (i) amplifier gain; (ii) emphasis/ de-emphasis of different segments of the audio spectrum; (iii) noise management; (iv) frequency response; (v) the audio signal sampling rate; and (vi) the number of bits per audio sample.
 406. The audio system defined in claim 401, further comprising a cardiac monitoring and external defibrillation system which allows an untrained human enabler immediate access to a medical professional who can and will remotely monitor, diagnose and treat a victim of medical emergency at one of a plurality of remote sites, said system further comprising: (a) at said second location: (1) a display device for displaying cardiac information from a victim for evaluation by said medical professional, coupled to said second receiving device; (2) a defibrillator control input device, coupled to said second transmitting device, responsive to said medical professional, for producing a defibrillation control signal for controlling the application of a defibrillation pulse to said victim; and (b) at each said first location, emergency cardiac monitoring and external defibrillation apparatus including: (1) a defibrillator circuit, having a control input coupled to said respective first receiving device, for generating a defibrillation pulse at a respective defibrillator circuit output in response to a defibrillation control signal received at said defibrillator circuit control input; (3) an electrocardiogram (ECG) circuit, having an ECG circuit output, coupled to said respective first transmitting device, and having an ECG electrode input; (4) a plurality of contact electrodes, adapted to be placed by a nearby enabler upon a chest wall of said victim, said plurality of contact electrodes being adapted to be arranged at separate locations on said chest wall for the receipt of ECG signals from said victim and for application of said defibrillation pulse to said victim; and (5) a connecting cable having a plurality of electric wires for connecting each of said contact electrodes to at least one of (i) said ECG electrode input and (ii) said defibrillator output; whereby (1) said ECG signals may be transmitted from said contact electrodes via said connecting cable to said ECG circuit and from thence to said second location, (2) said defibrillation control signal may be transmitted from said second location station to said respective control input of said respective defibrillator circuit and (3), in response thereto, said respective defibrillator circuit generates said defibrillation pulse for application to at least one of said respective contact electrodes, for resuscitation of said victim, via said respective connecting cable, wherein said audio system allows said medical professional to (1) determine the operability of the audio apparatus at a particular first location, and (2) communicate with said enabler when said particular audio apparatus is operating properly.
 407. The audio system defined in claim 402, wherein said second location further comprises third input device, responsive to said human operator and coupled to said second transmitting device for producing a transmission control signal and wherein said first receiving device is further coupled to said first transmitting device responsive to said transmission control signal, to retransmit said second audio signal back to said first location, thereby to determine whether each component of the system is operable.
 408. A communication system with fault correction means comprising, in combination: (a) a central station operated by a first person, comprising: (1) a first transmitting and receiving (T/R) device; (2) a first microphone, coupled to said first T/R device; (3) a first listening apparatus including at least one of: (i) a first loudspeaker, coupled to said first T/R device; and (ii) a first earphone, coupled to said first T/R device; and (4) an input device, coupled to said first T/R device; and (b) at least one peripheral station, operated by a second person comprising: (1) a second transmitting and receiving (T/R) device; (2) a second microphone, coupled to said second T/R device; (3) a second listening apparatus including at least one of: (i) a second speaker, coupled to said second T/R device; and (ii) a second earphone, coupled to said first T/R device; and (4) a display device for viewing text messages; (5) a text-generating device, coupled to said display device and to said second T/R device, for receiving at least one signal from said input device and, in response thereto, generating text messages for display on said display device; whereby, if said second person can not adequately hear said first person using said first microphone and said at least one second listening apparatus, (1) said second person may communicate said problem to said first person from said second microphone to said at least one first listening apparatus, and (2) said first person may utilize said first input device to send text messages to said display device, thereby allowing said first person and said second person to maintain two-way communication.
 409. The system defined in claim 408, wherein said text generating device has a memory which stores a plurality of text messages, and wherein said first person may communicate with said second person by selecting at least one text message using said input device.
 410. The system defined in claim 408, wherein said first person may communicate with said second person by selecting a series of individual text characters, using said input device.
 411. The system defined in claim 409, wherein said central station further comprises: (4) a display device for viewing text messages; (5) a digital memory device, coupled to said display device, said input device and to said first T/R device, for storing text messages; whereby said first person may view and select a text message for transmission to said second person.
 412. The system defined in claim 408, comprising a plurality of peripheral stations and wherein said first person may utilize said input device to generate a peripheral station selecting signal, thereby causing said first T/R device to select one particular peripheral station with which to communicate.
 413. A communication system with fault correction means comprising, in combination: (a) a central station operated by a first person, comprising: (1) a first transmitting and receiving (T/R) device; (2) a first microphone, coupled to said first T/R device; (3) a first listening apparatus including at least one of: (i) a first loudspeaker, coupled to said first T/R device; and (ii) a first earphone, coupled to said first T/R device; (4) an input device, coupled to said first T/R device; and (5) a display device, coupled to said first T/R device; and (b) at least one peripheral station, operated by a second person comprising: (1) a second transmitting and receiving (T/R) device; (2) a second microphone, coupled to said second T/R device; (3) a second listening apparatus including at least one of: (i) a second speaker, coupled to said second T/R device; and (ii) a second earphone, coupled to said first T/R device; and (4) a speech recognition device, coupled to said second microphone and to said second T/R device, for producing an output representing the text of the speech of said second person, for transmission to said display device; wherein, if said first person can not adequately hear said second person using said second microphone and said at least one first listening apparatus, said first person may utilize said first input device to activate said speech recognition device, causing said speech recognition device to convert said second person speech into text messages for transmission to said first person; thereby allowing said first person and said second person to maintain two-way communication.
 414. The system defined in claim 413, wherein said speech recognition device further comprises a logic device for the translation of one language to another; thereby allowing said first person to understand said second person, if said first and said second person speak different languages.
 415. The system defined in claim 413, comprising a plurality of peripheral stations and wherein said first person may utilize said input device to generate a peripheral station selecting signal, thereby causing said first T/R device to select one particular peripheral station with which to communicate.
 416. A communication system with fault correction means comprising, in combination: (a) a central station operated by a first person, comprising: (1) a first transmitting and receiving (T/R) device; (2) a first microphone, coupled to said first T/R device; (3) a first listening apparatus including at least one of: (i) a first loudspeaker, coupled to said first T/R device; and (ii) a first earphone, coupled to said first T/R device; (4) an input device, coupled to said first T/R device; and (5) a display device, coupled to said first T/R device; and (b) at least one peripheral station, operated by a second person comprising: (1) a second transmitting and receiving (T/R) device; (2) a second microphone, coupled to said second T/R device; (3) a second listening apparatus including at least one or: (i) a second speaker, coupled to said second T/R device; and (ii) a second earphone, coupled to said first T/R device; and (4) a keyboard for inputting alphanumeric characters, coupled to said second T/R device; wherein, if said first person can not adequately hear said second person using said second microphone and said at least one first listening apparatus, said first person may instruct said second person to use said keyboard to input text messages, thereby allowing said first person and said second person to maintain two-way communication.
 417. The system defined in claim 416, comprising a plurality of peripheral stations and wherein said first person may utilize said input device to generate a peripheral station selecting signal, thereby causing said first T/R device to select one particular peripheral station with which to communicate. 